I dont think he meant let it go back in the road. lol Whenever I find them in or near the road, I enjoy them for a few moments then help them on in the direction they were going but to a safe, happy location. In other words, just put it back in the woods.
If you do decide to keep it, don't get a heating rock. It's a turtle. Use either a lamp or undertank heater. You'll need a thermometer to meter proper temps. Temps are very important to an animal who's food will rot in it's gut if not given the proper temps. Always remember, reptiles can carry salmonella and parasites. There are rinses, etc to help with this. Be sure to wash your hands and watch your kids if you have them. Always supplement with fresh foods. Dont just feed prepared foods. Iceburg lettuce is worthless, also.
Anyway, box turtles are cool as hell. There is more than one kind of box turltle, too. One of the funniest things I saw one time was walking down a dirt road, hearing some noisies in the leaves and looking over to find two box turtles fucking. lol Funny stuff.