Yeah, you'll be suprised how much riding helps this kind of stuff (skids, track stands, etc.) even if you don't practice all of the time riding alone will help you with it. Besides, skid stops are far overrated, they eat away your tires and all for the sake of looking cool, and trust me if you aren't even able to do it then it doesn't look cool. Just get a front brake and learn to use it. I'll admit skidding is sometimes fun but I rarely do it because I don't want to go through the trouble of buy and changing a rear tire all of the time.