Collision in Blender

Hi there. Iv’e made a rough version of a map for my game in blender and Im wondering what would be a good way to do collision. I know in blender you can make collision boxes, but in unreal you can also do that. Should I just sketch out all the collision in blender? what about for small models? thank you

Have I gone at this totally wrong?

I would say to set up the collision in blender then export it to UE4. But I have been having problems with UE4 reading the collision I made. I haven’t tried it a while so I am not sure if this problem is still there. Or you can just set up the blocking volumes in Unreal which is what I ended up doing. For small models I just left the default collision that the engine gives it when imported in the level.