My PC doesn't boot up correctly 50% of the time

Here's my specs

I've had this PC for a solid ~3 years, using it daily with no issue, but lately i've had this problem where when i boot up my PC in the morning, 50% of the time it boots up wrong and is in an unusable state. It seems entirely up to chance. The following can happen:

• PC boots up, but the ethernet adapter isn't functioning whatsoever , and sometimes an external drive or two are missing
• PC boots up, but starting off the very bios it's INCREDIBLY slow (like 4-5x as long to boot up), and when it does boot up to windows, everything looks fine except the mouse is incredibly sluggish and freezes often, and as soon as i open the start menu it flat out bluescreens
• PC boots up perfectly normally

Usually, if i get any of the bad boots, i power it off and power it on again and it works fine. But then the very next day, the first boot has a chance of being a faulty one.

I have no idea what is caused by this. I was suggested to disable Fast Startup in the windows power settings, but that didn't really do much.

Any clues?