Error while installing anything

whenever I’m trying to install anything or update I’m getting this error :
E: Could not open lock file /var/lib/dpkg/lock - open (2: No such file or directory)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?

what is the problem can somebody please help… I’m complete noob.

https://support.endlessm.com/hc/en-us/articles/115000097483--TBD-Why-can-t-I-use-apt-get-dpkg-dnf-or-rpm-commands-

There is an updated version of this FAQ which is not yet published, so I’ll lift the text here:

Most desktop Linux distributions are oriented towards tech-savvy users and developers, but Endless OS isn’t your typical Linux distribution. We have a different target user. We don’t use rpm, apt, or any other packaging system. We use a read-only root file system managed by OSTree with application installed using Flatpak.

You may notice that the apt-get and dpkg commands are installed. This is because Endless OS is based on Debian, and these commands are used while creating Endless OS. Each release is a read-only snapshot, so you can use commands like dpkg -l which do not make changes to the system, but you cannot use commands like apt-get install.

For more information on the open-source software used to build Endless OS, see the Developers page on our website.