Starting a CS:GO server

hi all, I want to make a cs:go server, so I installed steam cmd the wrote the following:

login ******** **********

force_install_dir c:\csgo-ds\


app_update 740 validate

after that I have no clue what to do, how to start your server, does it need port forward,how to how port forward, editing the server, installing custom maps and running them, plz help me.
Thx in advance