Looking for a guide on how to make a blocky character creator

Looking for a guide on how to make a blocky character creator. Im looking to make something reminiscent of armored core with part selection but with customization blocks like in robocraft. I have never built a character creator before and Im looking for a direction to start looking in. The idea is to customize limbs with blocks and then weld all of the limbs together to create a machine. Ive been told this is possible but I have not taken any kind of formal training with unreal and have had a mismatched education so far.