Most likely in your first day of drum lessons, you're going to learn how to hold the sticks correct and do a full stroke, and learn to just basically how the coordination of hand to hand stick motion.
And the first rudiment that you're going to experience is called the single stroke roll, which is basically an alternate series, or an alternating series of stick motions back and forth, right left right left, or if you're a lefty you would start with the left hand, left right left right, and so on and so forth. And basically a single stroke roll will start slow, and you get it up to the point where you get it as fast as you can, and you bring it back down again. It will sound something to this effect.
Unlike a lot of other rudiments, there really isn't a lot that goes into a single stroke roll other than just staying clean, and making sure your sticks come to a similar height, and that you have a matching grip and a matching motion in both hands, and that you're alternating cleanly.
Other than that, there is not much more to a single stroke roll than just alternating strokes back and forth.