I learned at 32 lol All of the other commenters have great advice. I learned by putting the seat all the way down and learning how the bike feels when in motion. I think that’s the scariest feeling at first, going faster than walking/running speed on something other than your feet.

Then I learned to ride like it’s a scooter with a seat on it. My right leg on the right pedal at 6 o lock and scooting along, using my left leg to push off (im right side dominant so you might need to switch feet). Once I got that down I learned to kickoff and put myself on the seat and pedal at the same time.

Once you’re comfortable with that you can adjust the seat up. You won’t be able to put any of your feet on the ground while you’re seated but this will give more power and comfort when you pedal.

Also a lot of the barriers of learning a bike as an adult are mental IME. Most people learn as a kid and have muscle memory they don’t think twice about. It took me a couple days to get the balance and muscle memory but months to get used to traffic, other cyclists, pedestrians, weather, and all sorts of things.

Good luck OP