My screen turns on But just Black, NO caps lock, no num lock.

So one day, I had some RAM sticks lying around, so I decided to take it apart, there is one screw holding it together, so i unscrewed it. i saw that the RAM sticks i had didnt fit. so i put it back together, then i turn it on. Just BLACK there is one light at the edge of thr bottom saying it is on but no caps lock no num lock no external monitor, ABSOLUTELY NOTHING if anyone can help me that would be so nice. i am 10 years old, have a HP printer and no laptop. if this works then that would be so good. i have a Samsung galaxy Tab E and it has 8 GB Storage, OMG that is NO storage at all. it can barely save and print pdfs so i really need my laptop.