I have a troy-bilt riding mower and it sometimes gets stuck in gear and wants to keep moving whether it be forward or backward. I can put on the break and it still won't stop. I just had new drive belts put on. Could this have anything to do with it. If not what could be causing this to happen?

Did you have both belts replaced ?
And if so did you use after market belts ?

I did replace both belts I purchased them at a local lawnmower repair store.

This evening I jacked up the rear wheels and put it in gear and it did fine. It ran at full speed in forward reverse with no problem. The belts seemed to have moved as they should

I them turn it off and then release the brake then the drive pedal becomes hard and when I ran it kept moving forward while idling and I the brake wouldn't stop it. I am so confused... any help would be appreciated... Thanks

Sounds like the wrong belts . Or check the bottom belt in the rear make sure its not rubbing on something.
Sounds like it could be rubbing on a belt guide.
What you are describing is what happens with wore out belts
The belts should be wide about 5/8 s inch .make sure they didn't give you 1/2 inch belts.
Luck

I doubled checked the belts. They are the correct replacement belts measuring 5/8 and the replacement numbers match. I tried a few other things and what I can tell is when I install the transission drive pulley is when everything tightens up. I noticed due to the tension on this belt it shoves the spacer in the variable speed pully up pushing that pulley out some. This is also when the pedal gets drive pedal gets stiff.