GMS 2 3D tutorials / learn the basics

I've been using GMS for about a year now having Zero previous coding knowledge. I got my start following along the simple 2d arcade style game tutorials and went from there. I really want to make a 4 player FPS deathmatch game. Very simple 1 weapon, 1 map and go from there, but I can't find a single video or written tutorial on where to start. Can someone point me in right direction? Or does anyone have some commented demo code I can try out to get an understanding of how 3d works? Thanks in advance to anyone who takes the time to reply.