You probably bricked the machine by accidentally touching one of the other components. 1. 1st Try putting the write-protection screw back in & reboot. If it still doesn’t boot, you’ve killed the machine. If it does boot, then you’re ok and you can go back to using it as before. 2. Pull out the Hard disks/SD cards. Look at and pull the RAM memory and put the rest in the recycling bin. If you’re feeling savvy, you can try to resell the RAM by looking up the model numbers (printed very tiny on them). 3. Buy an external SSD enclosure to put the old hard drive in (it’s probably still good), and you can use it as a portable external drive. 4. Buy a new computer.