It is a little late to ask since you have already joined. Yes it works!. It was created for self defense. Others may use a portion of it for sports competition, but the origin and purpose is for real self defense.
I like the fact that Tang Soo Do normally has pretty hard contact sparring sessions. This should ready you by getting you used to taking a punch or kick, which is probably going to happen in a "real" fight. Callsign is correct in that if by "real" you mean a counter assault situation like a dude trying to get you into a car or really trying to kill you then you will need to practice scenarios outside of the standard dojo one on one, both guys playing by the rules stuff. But all in all, for school yard fights, tough guy at a bar tool measuring contests and the like, Tang Soo Do, taught and studied diligently, will prepare you to a decent extent. Have fun and train hard!
Some of the kicks you learn in Tang Soo Do will work in "some" situations. Tang Soo Do is the first martial art that Chuck Norris ever mastered, and in his prime he was able to throw some devastating spinning back kicks. What I like about Tang Soo Do best is the amount of flexibility you can develop. Many martial arts are great, but they lack the emphasis on stretching to make you limber enough to throw some devastating kicks.
In addition to being able to hurt an opponent, kicks are great for creating distance between you and your opponent. Distancing is important to minimize the amount of abuse you take in sparring or fighting, and distancing is critically important to allow you to escape from a dangerous situation.
Eventually, you will want to crosstrain in other martial arts to become a well rounded fighter, but Tang Soo Do is great for developing flexibility and high kicks that an opponent who doesn't know Korean martial arts may not be able to anticipate.
If it's trained in a way that addresses "real fights", then yes. The basic strikes are mechanically sound. The defenses may be a little iffy, depending on how their taught, but that's really up to the teacher/school. But what it comes down to is how it's trained. What's your sparring like? Do you do any scenario training? Do you hit striking tools (mitts, bags, etc)? Do you address common attacks? And most importantly, do those defenses make sense? If you're told to take three motions to defend against one motion, it's very likely it will have trouble working in real time, for example. But fundamentally, the techniques are sound.
Just curious because I just joined tang soo do
