Procedurally generating a level using pre-made models

But how can I start implementing it? I couldn’t find any tutorials or any discussions about this subject. The connection points will be set in the BP of any “terrain piece”, it’s just a matter of connecting those. However, I do not know how to do it in Unreal.

I understand that to attach something to a mesh, or skeleton, sockets are used, but I couldn’t find a way to add a socket to a BP Actor class.