How do I create a mesh collider?

Questions & Answers
1

I’m going through the car tutorial and have come to the part where it says “Go to the Component/Physics Menu and click the MeshCollider to add one to the game object,” but the program is just literally not letting me do this, why might this be?

2

don’t you forget to select an object before adding component?

3

So what’s the deal with Unity mesh colliders then? Does it literally use the imported mesh as the collider too? I only ask because in most engines the collision mesh is a simpler mesh so this really confuses me