Help with creating a tank

Hi All!

I’m attempting to create a tank following this tutorial: Blueprint Creating a Tank | Live Training | Unreal Engine - YouTube
I have assembled the tank using static meshes, however I can’t seem to get it to collide with my world. I’ve tried several things but none of them have worked out.

Also I don’t know how to limit the barrel’s “look up and look down” amount. It keeps rotating through the turret.