iMac 24" have glitching screen

iMac 24" (M1 2021) Sequoia 15.1

One day I wake up and see my screen get glitching + flickering like this (dim in some part of the screen + Aurora like)

Facing towards the iMac, the top right in the front part of the screen only there gets very hot. So I think this maybe an overheated problem, but it's weird when air vents don't respond or work.

I had run an Apple Diagnostic to see if there is a problem with hard drive but it's says ADP000 (No issues found). Also restart, already updated MacOS, checked for malware but didn't work.

The more I spend time working on it, the more I can smell a burning scent coming from it (it really is, makes me worry to continue using it).

Thank you for every help!