GVWR is the Gross or maximum weight it should ever weigh.
Hitch weight for a travel trailer is usually about 12% of the trailers actual weight.
That weight is added to the tow vehicles weight. You will find that the sum of the axle weights is less than the trailers GVWR. The difference is tongue weight.
As for your tow vehicle, you need to load it like your going camping, that means full gas tank, the entire family, plus all your stuff that will normally be in or on the truck and go to the scales. They will give you your total weight. Now looking on the drivers door post you will see a federally mandated sticker that gives lots of informatin, including the GVWR. Subtract your scaled weight from that number and you will have the available payload. Meaning how much tongue weight you can add to the vehicle before you exceed the manufackturers GVWR. If you assume 15% then it is a pretty simply math to determine how much trailer you can comfortably tow.
Got it now?