3D is definitely not the easiest thing to do in GameMaker, but that's why I went with billboard sprites, like FZero or Super Mario Kart.
I am a freelance developer, however.
For the camera, it's actually easier than you would imagine, as cameras are automatically in a 3D space. By default they look 2D as they are by default set to orthographic. If you have a discord you can message me on there about it. My username is dreammixgames