Before you start inline skating, make sure you know how to stop. A brake may be mounted on either skate.
Most skaters prefer it on their stronger, dominant foot.
In any case, braking requires practice, practice and more practice. Standard Brakes A. Lean forward at the waist and extend braking foot forward. B. Shift most of your weight to the rear skate. Keep both knees bent. C. Lift the toe of braking skate, keeping its rear wheel on the ground.