OK.
If you get under the trailer, at each corner you will see a curved metal conduit that conduit needs to be pulled back and 30W motor oil needs to be squirted into the conduit around the large spring that pushes on the corner to raise the roof.
Just remove the two screws and pull the conduit down...
Then squirt some oil into the conduit...
After you are done, push the conduit up and secure with the two bolts.
Now, under the trailer in the center is the track area where the cables go though, on the front and rear are two zerk grease fittings. Pump a lot of grease into each fitting. If this has never been done before, you will probably use an entire 14 oz tube of high pressure lithium grease or synthetic) for each fitting.
It gets easier from here.

Under the winch motor on the trailer frame is a pan held in place by 4 screws. Remove those screws, drop the pan, and then spray a lube such as WD-40 onto the drum and bottom of the gear assembly you will see when looking into it. Then replace the cover.
Now, on top of the winch cover, on the left side as you are looking at it, is a round cover (about 1.5 inches in diameter). Pop that cover off, and make sure it is filled with grease (high pressure lithium grease is ok).
You should also have the axle bearing lubed too. You probably have the EZ lube system, and can just pump grease into the zerk fittings until the old grease starts to come out the outer edge of the axle.