Gmod dedicated server questions

yeah i have a few questions regarding the gmod dedicated server setup

  1. how can i make so in my server you can kill each others`??

  2. how can i change my server to have a password?

  3. (Edited)

ps: please let me know if this kind of thread has already been posted.
and by the way, just so you now i followed this tutorial on how to make my own dedicated server

c’mon people if you dont know maybe you can tell me some other thread

… You really can’t have your own server if you can’t figure these things out.