key oard is not working and I need to enter a pssword to get into my computer. what do I do

If you have access to a USB keyboard that should work. If you don't have one they are available from multiple sources. An inexpensive keyboard is fine.

If you don't have another keyboard but you do have a usb-hub: give it a try to connect your keyboard to the Mac through this hub

If that doesn't help: try this

1. Hold down the power button until your Mac turns off
2. Unplug the power cable.
3. Wait a minut and plug the power cable back in
4. Wait a minut and use the power button to turn your Mac on again