To boot into safe mode try ONE PER TRY (so if you get to the screen ignore the rest) of these, in order until you see a blue menu asking what to do (I cannot tell if you can reach some of these so I'm putting most of the ways) :
1)Shutdown PC, hit the power button and spam the F8 key on the keyboard until you see the Windows logo (or its loading animation, the circles), if you are lucky and your PC is kind of sluggish to POST it will work
2)Start>Settings>Update&Security>Recovery>Advanced Options>Startup Settings>Reboot
3)From the lock screen hit power icon, and hit Restart while holding the Shift key. (You can do the same while logged in, from Start)
4)Shutdown PC. Press power button. When you see any signs of booting (for example, the motherboard manufacturer's logo) hold the power button until it shuts down (if it restarts hold the button once more and don't let it get into Windows login screen or you'll start again.) Then power it up and hold power button when you see the screen once more. So in a total you should have restarted it twice. In the third restart just let it boot. It should kick Automatic Recovery (which is nothing to worry about, just wait until done) and when it's done youll see the menu. (Nutshell: Boot, when you see anything on the screen force shutdown, do it once more) And hit Advanced Options.
If you could do that you should see a fully blue screen (not a BSOD) asking you what to do. Be warned that you cannot use your mouse here, you will need to use the number keys. Press 4 for Safe Mode. See if problem persists.