This being your first MacBook, having it for two months, and you being a college student aren't likely to play a part in getting a free logic board. That's a fairly expensive repair.
With water damage, there isn't any way to know with certainy what may or may not have been impacted. Replacing the logic board does not guarantee that your system will function properly. Depending on how extensive the water damage was, other components may have been damaged.
Exactly how was it water damaged? A few drops of soda on the top... a drop into a full bathtub? The more extensive the accident, the more likely that water may have gotten into everything.
Also, how long ago did this happen? One of the most important things NOT to do after contact with water is turn your machine on. It should be thoroughly dried (for days) before attempting to turn it on. There is the possibility of causing more damage if you turn it on while it is still wet. If the water damage happened only recently, you may want to try removing your battery, leaving the lid up, and letting it sit for a few days. Systems will sometimes recover on their own when they dry out.