Dropped iPhone 7, turned off, then heated up. Now wont turn on

As title mentions, dropped it, took a few seconds for it to turn fully off, obviously screen cracked, and then once off got really hot for about 30 mins minimum... Tried to turn it on and plug it in but completely dead. I am going to open it up, as its something I want to learn, and see what needs replacing. If i send a picture of the inside will someone on this community be able to help me decide what needs replacing whether its battery etc?