How to not be hungry so much?

No easy answer. Different people's brains are wired for different levels of appetite. In addition to today's medications, the one time-tested method of curbing the munchies for most (not all) people is really intense aerobic exercise. You'll not only burn calories, you'll feel less of an irrational need to overeat.
To decrease hunger. 1. Portion control. If you reduce the amount you eat, your stomach's thermostat for hunger will find less food more satisfying within just a few days of eating less. 2. Hypnosis 3. Redefine hunger as only occurring when the stomach grumbles and gnaws at you. If you want food and you don't have signals from the stomach, you aren't hungry. You are craving food.
Hunger. Appetite suppression is risky if using meds and these are usually not very effective in the long term. The new long-acting incretin class of drugs may help but the sustainability of their effects on weight loss is an open question.