Hy I am making a video game character and I'm on the animation part, specifically rigging. I am sure I did everything necessary and looked at similar questions to. As the title says the mesh does not move with the bones. Sorry, I'm used to 2D, but I REALLY want to get into 3D and know everything necessary to start except for rigging of course. The rigging part is hard and I don't know why.
your geometry is unsuitable for rigging. Imagine, that bones moving with vertexes. In your case is impossible bending mesh by bones correctly, because mesh have really bad topology for animation. And this is the reason why Blender can't assign vertexes to bones and give error message.
Normally you can use "Automatic weights" feature in Blender. Select mesh, press "SHIFT+LMB" select armature. After press "CTRL+P" assign mesh to bones. But this doesn't work in your case.
I hope this help you. Also you can find a dozens tutorials about this theme all over the internet.