I have this plugin installed but i don't see anywhere where you can enable it (chat command, console command etc) Anyone know it?

Its all listed in the documentation on the plugin page . you (as admin) grant the permissions as needed in chat or console

Uh I looked and if only has the perms? Or are those the commands you put into console for it to work?

Merged post

Okay it works now, ty for helping

I will give you example, I use it to give rewards to players who are long term, i have set up "ranks" for hours on server and create the group name of that rank, I then grant that group (and the ones above it) the permission for infinite ammo or one of the other choices,
it mind seem "OP" but they have to be on the server for 500+ hours to get it,
So i type (in chat) /oxide.grant group maximus infinity.ammo
I should then get a confirmation in chat that the group has that permission