Setup DHCP or static IP address from command line in Linux

Did you ever had trouble with Network Manager and felt that you need to try to setup DHCP or static IP address from command Line in Linux? I once accidentally removed Gnome (my bad, wasn’t paying attention and did an apt-get autoremove -y .. how bad is that.. ) So I was stuck, I couldn’t connect to Internet to reinstall my Gnome Network Manager because I’m in TEXT mode network-manager was broken. I learned a good lesson. you need internet for almost anything these days unless you’ve memorized all those manual command.