>>76366168 (OP)Get a bike with straight bars as they offer more control and make it easy to peddle standing up for more power.
Set the bike to a low gear and set the seat a bit too low that you can touch the ground with your feet without going on tippy toes and just roll around a bit to get a sense of balance. The bike will balance itself at speed so if you can balance at low speed you'll do ok when you start peddling faster. Make sure your front brake isn't too powerful as new riders tend to panic brake and fall over the handlebar is the breaks are top good in the front. Keep your feet close to the ground while you test out your balance to be able to catch yourself early when you feel that you're falling to one side.
I recommend getting the somewhat expensive but puncture proof tires made by Schwalbe called "Marathon plus" or similar to not waste time and money on fixing tires. I've been riding my first set for many years now without a single puncture and I had punctures at least once a month before I decided to shell out the money for the puncture proof tires . I'm forced to ride through glass shards all the time but now I don't get anxiety from it, especially on longer tours.
Have fun, fren, riding a bike in nature is such a good use of one's time and a fun exercise to boot.