You should try a stair gap to flat, 5 or 6 would work best. Wheelie right before top step. Seriously, try learning on a mt bike. Helmet and flat pedals on a smooth, slightly uphill grass slope. Get in an easy gear, strong foot forward at top of stroke. Pedal hard, pull up on bar, keep fingers on rear brake to prevent looping out. Let me know when you can pedal more then 3 or 4 times, I've been trying for about 40 years.