Singleplayer mods/menu

I wanted to make a redm server for me and my friend to have fun etc. so my question was would it be possible to install a trainer like the jedijosh trainer

+, i also want this

Yes and no. We didn’t find a trainer that we were happy with so we just created one. It’s for Developer/development only however. So, my suggestion is to take the module you want (trainer or not) and simply try. You’ll need some basic programming/debugging skills to do this however. Never too late to start and with some googling you can find any answer you need.