I cant play any steam games or any other games what do i do?

i started playing a game called garrys mod and it worked at first then my keyboard stopped working so i thought it got unplugged. it wasnt so i started to change the keys so w is to move forward it still was. i went to change it so i hit W and it said 5 i changed it again with the same key and it said 6. i dont know what to do