How would I make a building system similar to that of Road to Gramby's?

You can write your topic however you want, but you need to answer these questions:

  1. What do you want to achieve? To create a system thats similar to Road to Gramby’s. Has attachment points, spawning, grabbing, and when item grabbed, it goes into players hand.

  2. What is the issue? above.

  3. What solutions have you thought of so far? Looking thru devforums, reddit, other game dev places.