i just read some advice above that scares me. I ride bmx trails, some are rather big to be honest, but i’m guessing you wont be jumping anything like them, more likely it will be mellow lips, and long mellow landings. Definitely don’t try to land front wheel first when you start to learn! this is asking for trouble in my opinion. Try to get used to jumping a tabletop somewhere, and keeping the front wheel level with the back, until you can spot the landing, then you slowly try to land front wheel at the same time as the back, and when you get really confident, land front wheel first. Then when you get to a similar sized double, your best bet is to follow someone a few times towards the lip, but stop before hitting the jump, this will help you to judge speed etc. then when you hit the jump you can use the ‘spotting the landing’ technique. This is important, to make sure you dont come up short on the front wheel, as you will almost definitely go ove the bars. If you just hang up on the back wheel, the likelihood is, youll be fine, it wil just be a bit harsh, I managed to come up short with the back wheel ( as in right into the vertical part on the back) on a 20 foot racer, and roll away. The front would have been a different story altogether.
That probably makes no sense though unless you have someone show you the techniques im talking about.
Andy