by running this command curl -sL https://deb.nodesource.com/setup_10.x | sudo -E bash - and sudo apt-get install -y nodejs. this following is occurs may be this is error in the end.

 # Installing the NodeSource Node.js 10.x repo...  ## Populating apt-get cache...  enter code here`  + apt-get update  Hit:1 https://deb.nodesource.com/node_8.x xenial InRelease     Hit:2 https://download.sublimetext.com apt/stable/ InRelease  Hit:3 http://archive.canonical.com/ubuntu xenial InRelease  Ign:4 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial InRelease                                                                        Hit:5 http://in.archive.ubuntu.com/ubuntu xenial InRelease                                                                                         Hit:6 http://security.ubuntu.com/ubuntu xenial-security InRelease                                                                               Hit:7 http://in.archive.ubuntu.com/ubuntu xenial-updates InRelease                                                                              Hit:8 http://ppa.launchpad.net/webupd8team/java/ubuntu xenial InRelease                                                                    Hit:9 http://in.archive.ubuntu.com/ubuntu xenial-backports InRelease                                                                            Hit:10 http://in.archive.ubuntu.com/ubuntu xenial-proposed InRelease                                                                               Hit:11 http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu xenial    InRelease                                                              Ign:12 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial Release                                                                         Ign:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages                                                             Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages                                     Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages                                     Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN                                Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en                                   Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata  Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons    Ign:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages        Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages  Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages  Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN  Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en                                   Ign:20 http://dl.google.com/linux/chrome/deb stable InRelease                                                                   Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata                                      Get:21 http://apt.postgresql.org/pub/repos/apt xenial-pgdg InRelease [51.3 kB]                            Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons          Ign:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages  Hit:22 http://dl.google.com/linux/chrome/deb stable Release  Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages                               Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages  Get:24 http://apt.postgresql.org/pub/repos/apt xenial-pgdg/main amd64 Packages [109 kB]  Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN  Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en  Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata  Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons  Get:25 http://apt.postgresql.org/pub/repos/apt xenial-pgdg/main i386 Packages [109 kB]              Ign:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages  Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages  Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages  Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN  Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en  Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata  Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons  Ign:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages  Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages  Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages  Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN                                                          Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en                                                             Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata                                                      Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons                                                         Err:13 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 Packages                                                             404  Not Found  Ign:14 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main i386 Packages                                                              Ign:15 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main all Packages                                                               Ign:16 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en_IN                                                          Ign:17 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main Translation-en                                                             Ign:18 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main amd64 DEP-11 Metadata                                                      Ign:19 http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial/main DEP-11 64x64 Icons                                                         Fetched 269 kB in 34s (7,908 B/s)                                                                                                               Reading package lists... Done  W: Target Packages (partner/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target Packages (partner/binary-i386/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target Packages (partner/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target Translations (partner/i18n/Translation-en_IN) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target Translations (partner/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target DEP-11 (partner/dep11/Components-amd64.yml) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target DEP-11-icons (partner/dep11/icons-64x64.tar) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: The repository 'http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu xenial Release' does not have a Release file. N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. N: See apt-secure(8) manpage for repository creation and user configuration details. E: Failed to fetch http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found E: Some index files failed to download. They have been ignored, or old ones used instead. W: Target Packages (partner/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target Packages (partner/binary-i386/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target Packages (partner/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target Translations (partner/i18n/Translation-en_IN) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target Translations (partner/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4  W: Target DEP-11 (partner/dep11/Components-amd64.yml) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 W: Target DEP-11-icons (partner/dep11/icons-64x64.tar) is configured multiple times in /etc/apt/sources.list:45 and /etc/apt/sources.list.d/xenial-partner.list:4 Error executing command, exiting 

help me i am using ubuntu 16.04