This is the conventional way to “jump” curbs. It’s all about timing. As you come towards the curb you need to get in a wheelie, while trying not to loose speed. Then the second your back wheels hit the curb (they need to hit at the same time), you push your wheels forward while keeping your center of gravity over the back wheels. Caution: some people lean too far forward and loose traction on their back wheels. Good luck and practice a lot. For most of these tricks, I like to find a place that’s not busy, that way when you screw up, you don’t have a hundred AB’s trying to pull you up a curb you’re trying to hop.