Yes, to inspect/replace the belts, you remove that black plastic cover.
Usually, one shaft comes out of the engine and has a double pulley on it. One belt drives the auger (when engaged) and the other drives the wheels, again, when engaged.
Make sure the double pulley on the main shaft lines up well whith both belts. If this is off, it can throw a belt and or chew them up really good if they are not aligned properly.
And just be aware, that on many models, when you remove the bolts on the case to replace the auger anbd drive belts, you are essentially splitting the machine in two. If the machine actually comes apart into two (heavy) pieces, it's best to have two people to put it back together again.
In other words, replace both belts at the same time and save yourself some headaches.
Our machine is a 1984 John Deere 1032 which breaks down a lot now. I've learned a lot from fixing it. A LOT
--- Bror Jace