Beginner-friendly rollerblades come equipped with heel brakes, which you can rely on when you need to stop. To stop with your heel brake, bend your knees slightly, push one foot forward, and tilt your heel toward the ground. Let your heel brake drag along the ground until you come to a stop.  You can also stop on rollerblades by dragging one foot behind you and turning it sideways, with your toes pointed out. In this stop, you want to use the sides of your wheels to create enough friction to stop.