I am a newbie in linux and I don't know how to open the Ubuntu Software Center via Terminal!! Please help
I'm not sure why you'd want to, but
should do it. If you want to use command line to install a package then the correct way to do it would be
sudo apt-get install package-name
sudo apt-get remove package-name
to remove it. If you want a text based package manager then you could have a look at aptitude:
Times have changed, and with them, the answer to this question. In desktop Ubuntu 21.04, it is still possible to install Ubuntu Software Center. Since that is the program specified by the original question, the answer is that you run it from the command line, first by installing it via:
sudo apt install gnome-software
and then by running it via the following command, with or without
You can also run it by using Show Applications → Software icon (white suitcase with aqua circle).
Since Ubuntu Software Center is no longer installed by default, this question (if asked today) would refer, instead, to the Snap Store. If it was not present, it would reportedly be installed via:
sudo snap install snap-store
In that case, the answer is that you run it via
Or you could click on the suitcase icon, in this case an orange one bearing the letter A (short for "Snap" in Latin, perhaps), whose tool tip says (of course) "Ubuntu Software".