Most rats will want to stay there and cuddle up. To make sure your rat gets enough exercise you can encourage him to play little games. Some rats like to play with a little ball or will want to just chase around. You can train your rat to come to you on command. Always reward with a treat.
Rats are very curious and like to explore their surroundings.
Rats are also natural chewers so to prevent them from chewing on electric cords, furniture and other things, try using some bitter apple, which is available at most pet stores. Apply it to any object that you don't want your rat to chew on. You will want to unplug all unnecessary lamps and appliances. You will always want to keep a close watch on your rat. The average rat has a life span of around 2 to 3 years.