Device Not not working or turning on ( not an easy fix)

Have you tried turning it on and off?

Just kidding

But all jokes aside, by " I did all the tricks I found online, nothing worked. I recently bought a new battery. Changed the old battery for the new one and the device still won't charge or even turn on.", you mean you never went to an expert before changing your battery? Changing batteries is always a risk (plus it's probably the reason why your phone overheats). If you've come to a point where you consider changing batteries, then you might as well buy a new phone.

Whenever you've come to a point where you're helpless and you really can't fix your problem, it's best to seek help/guidance form an expert. Yes, there are lost of helpful info on the internet, but it still won't beat years of experience.