the door may have come off the track. it generally needed 2 persons to get it back on the track.
There are several things that could go wrong with a garage door. Can you explain it in more detail?
It could just be a breaker. Try flipping all the breakers off and back on. Sometimes a breaker can be tripped but it doesn't look like it, so flipping it off and back on helps. You know.... Start with the simplest scenario first. 😂
If its the unit, you might need a new opener.
What exactly is the problem? If you have an automatic garage door opener with a remote, it could be as simple as changing the batteries in the remote. Is it off the track? Is it the automatic opener? More details please!
Garage doors are one thing that I'd advise against DIYing. If the problem has anything to do with your springs, I'd get a professional in to do it. Garage door springs can be really dangerous, and they're one of the things that can kill unsuspecting DIYers.
What exactly is happening that your garage door isn't working?
This is likely best left to the pro's as it could be a myriad of issues or a combination of issues.