>>1819174>>1819179It just takes practice. People who had coaster brake bikes as kids usually pick it up in a snap. For learning/'easy mode' there are a couple things you can do that alter how much grip your rear tire has.
Lean your weight forward (this is the universal advice), and you can also inflate your rear tire to max/near max. Both of these will reduce the rear tire's contact patch.
You can also try on a less grippy ground surface. When I was learning I mostly used a church parking lot that was blacktopped (that super black, smoothest asphalt), and a crushed limestone road that went to an abandoned farm (not my pic, but similar). If you're on pavement, you can also take a spare water bottle and make a wet patch on the ground.
Maybe check out that FOAD video on Youtube. There's a part where he talks through slow-mo clips, you might find that helpful. If you're unable to get it, even after trying all the tricks, you need more leg strength.