The two sentences are fundamentally different: I will make you.... it means this is what I impose upon you (like an order) that you have to follow. I will let you... means I give you the authorization to do it. Although, I will make you make sound kinda weird because of make used twice back to back 😁😁

I agree with Armin. The phrase "make sentences" itself sounds slightly stilted to me. It might be better to say "create sentences", "invent sentences", even (more colloquially) "come up with sentences". That would help you avoid using "make" twice.