When I put it in reverse my brake lights work but the reverse lights don't come on. also the front side markers don't work. What do you all suggest I check? I was thinking to check the bulbs but is there a fuse that could have blown? Thanks.

Do the tail lights work?
Use a test light to check all the fuses
Check the sockets for corrosion
Use a test light to see if you have power at the sockets
If yes, check ground connection
If good, replace the bulbs
If you are getting no power at the sockets and the fuses are good, then start at the switches and check to see if power is going in and coming out.
Use a wiring diagram as a road map to help trace the circuits.

If you have the towing module disconnect it and retest.

The brake lights work, I pulled on of the bulbs and it looked good. I checked the sockes for resistance with a voltometer and got .005 ohms, it was the same reading with the key on in reverse as it was with the key off. So do you think I should start checking switches?

I checked the sockes for resistance with a voltometer and got .005 ohms, it was the same reading with the key on

Never try to take a resistance reading with power applied to the circuit! The meter uses it own power to take this reading and injecting an external source will result in erroneous readings and may even damage the cheaper multimeters.

Just check for proper voltages and replace the bulbs.
Good luck