If you want to run commands in the background in linux you can use screen or tmux. But what is with started processes like a long update/upgrade command. It is bad to abort it so you can put this running process into the background.
1) Pause process: STRG + z
2) Run process in background: bg
3) Don’t kill the process on logout: disown
List of background tasks : jobs
Process in the foreground: fg