Sometimes on a really old netbook I had years ago, I'd bluescreen from trying to enter Fluorite Plains, haha. Other times i'd get them too, but never randomly out of nowhere
There was always a pattern. if i went to certain websites, played certain games, it'd bluescreen or overheat.
If it bluescreens and restarts on startup your hard drive could be having issues. Also, check what type of bluescreen it is. Usually it says something about a crash dump.
Does it turn on quickly, then just turn off?
Are the fans really loud and such on startup despite running almost nothing?
Does it freeze after being on only for a few minutes?
Try and download a program called Priroform Speccy. Check the temperatures of your cores, motherboard, and processor. If they're above 60-70 average without you running anything system intensive, it could be a number of other problems including a bad processor, which happens because it could be caked with dust inside therefor preventing your computer from cooling properly.
I really reccommend taking it to a repair shop. Sometimes the littlest, most unexpected things cause the worst problems for computers. Especially laptops, as everything is integrated. If it were a PC, you could just rip out whatever is dieing, buy a new one, stick it in there. Done.