How to install a new gamemode and make it work?

Hey, I have a custom game mode, and I put it in the Gamemodes directory, but how do I make it default start off with that game mode?

Also, if anyone knows, how do I add myself as admin with ULX mod. I have it, but I’m not admin.

Q1) Add +sv_gamemode “Gamemode” to srcds.
Q2) Use rcon to do “ulx adduser DrMelon superadmin” or w/e