Before doing any of the following, create a restore point on your system and back up any files you would not want to lose.

Download and run malwarebytes.com, just to make sure you don't have any bad actors on the system. If you think it's overheating, run "hwmonitor". It's on my system but I don't know if it came with windows or I downloaded it. Make sure temperatures are in range for the system you're running. Blow out dust from the intake and outflow areas of your computer (CPU fans, heat exchangers, exhaust fans). You may have to take the cover off of your system to get to some of these components. DO THIS OUTSIDE and/or wear a mask!

Try running Device Manager and see if any devices have a red or yellow alert symbol. If so, you can try reloading drivers, or removing and re-adding the device (be careful there - you don't want to remove something you can't easily re-add).

You could have a bad RAM (memory) chip, or one that's not seated properly. If you're comfortable with doing so, and if your RAM config allows it, you can try removing one memory stick at a time and running with less memory for a while, to see if the problem recurs when a specific stick is in the system (but not when it's removed). If that's the issue, a quick trip to a computer store will take care of that.

Try restoring from an earlier restore point (not the one you just created) or do a full system reinstall (drastic, but sometimes easier and necessary).

Those are just a few things you can do. There are ways to analyze "blue screens of death" and error codes, but your description makes it sound like you're not running into any of that.

And, of course, if you don't feel like doing any of the above, just take your system to a local computer store and let them figure it out. It will cost you, yes, but let's face it... they're professionals.

Good luck -- barry