Good advice so far. Because they are a more nocturnal species and do very little basking, UVB lighting isn't required however, it can't hurt. I have always offered my Stinkpots UVB lighting just for the heck of it.
Wild caught individuals can be switched on to pellets pretty quickly. Newborns however sometimes can be stubborn. If you're purchasing a stinkpot try to get one that is at least a few months old and eating well. Make sure to ask the place you buy it from what they are feeding it. My pair is on a diet of Reptomin, cichlid and koi pellets, freeze-dried shirmp, frozen shrimp, crickets, earthworms, dubia roaches, pond snails, earthworms, fish filets and shrimp pellets.
These guys can be really active and really do enjoy the space to poke around and explore. They're not much of swimmers so a shallow tank is fine plenty of rocks and driftwood to climb on. A 40 gallon breeder aquarium is a good size of the life of the turtle. I keep my pair in a 100 gallon rubbermaid tub. You should supply a basking spot for the turtle especially if it's young even though they may not use it at all. For babies to yearlings it's best to keep the water temperature in the high 70's and for adults the mid 70's is fine. They are messy just like all water turtles so whatever your volume of water is I recommend you double the filtration.