Iphone 12 overheating?

Ive had the iphone 12 for 2 years, Honestly its put too much that i might get rid of it… The iphone overheats like crazy so much to where it literally burns my hand even if the phone is shut off it still heats up!! I've tried everything replacing the charger while im on that the battery life is dropping so fast if i use the phone for longer than an hour i can literally see it go down few minute by minute, is there anything to solve this? or do i just get rid of the phone. it overheats the 5g is barely faster than 4g LTE this is getting annoying, my hand has several burns that i could go to the doctor for and not to mention the glitches that the phone goes through like my wallpapers wont work and its just black most of the time I've had to reset network setting like 10 times every month and so much more. please tell me there’s something i can do and that i didn't spend my paycheck on a phone that will just give me burns and barely works!