Hey there Stelios!
My name is Miguel Ángel and I'm an independent advisor, also a Microsoft user just like you! I'll try to help you today with your issue.
This normally happens when Visual Studio is compiling codes, and therefore the CPU usage is obviously high. Are you creating and compiling any kind of code or program?
Please, do make sure that all your Windows Updates are installed (Settings > Update & Security > Windows Update), and make sure to run a Windows Defender check to see if there's any malware causing this. Let me know about the results of both actions.
I'll wait for your reply! Don't worry, everything will be okay :)