I have an older power drill and shocked that it doesn't have a reverse switch? Can't find a manual online. Drill bit is stuck. Now what?
Use the chuck key to undo the bit? Otherwise vice grips as all ready stated in the case of drills with chuck keys once the bit is done up with the key you wont be able to hold the chuck to undo it if it had reverse anyway. If the drill isn't double insulated you shouldn't be using it anyway. Buy a battery drill unless you want to drill lots of big holes thru heavy gauge metal.
It uses a chuck with the key. The key can be used to reverse the chuck and release the drill bit.
Use a pair of vice grips and pull it out
Get a drill motor with a reverse and chuck it on the bit.
30 years ago it was UNCOMMON for drills to reverse, and MOST used a 'chuck key' to secure or loosen the bit. Note: The drill is fine, your understanding of how to operate it is lacking.