Long time street-skater here (30+ years). Not sure that stuff would help as it's pretty different rolling around in a gym vs. getting thrown off your board at 20mph. It also might actually make you ride over your head because you think you can bail and not get hurt. I also don't think pro skaters (inlines/etc...) are good examples because their skill level is already so high; they are operating on a totally different level. They already know how to fall really well because they've fallen a ton. Also, if you are worried about getting hurt, you probably shouldn't ride a skateboard.
The best preparation is just to get a regular skateboard (not a long board) and skate around on it on the sidewalk. This will help you get the balance and board handling down.
I highly recommend learning how to ollie on the regular board. The falling you do in learning how to ollie will help. Even if you can't ollie a boosted board, the board control you learn will help you manage riding over rough pavement. Also the ollie motion of shifting your weight can be used even on long boards to manage obstacles.
Finally, on the regular skateboard learn how to power slide. This will teach you how to balance your weight if the board is sliding sideways.
The best preparation is just to get a regular skateboard (not a long board) and skate around on it on the sidewalk. This will help you get the balance and board handling down.
I highly recommend learning how to ollie on the regular board. The falling you do in learning how to ollie will help. Even if you can't ollie a boosted board, the board control you learn will help you manage riding over rough pavement. Also the ollie motion of shifting your weight can be used even on long boards to manage obstacles.
Finally, on the regular skateboard learn how to power slide. This will teach you how to balance your weight if the board is sliding sideways.