For a long time I cannot avoid eating junk food (burger king etc ...) which increases my obesity problem and other health problems.
Does it happen to someone else?
I had the same problem. I lost 80 lbs in 3 months (went from 275 to 195lbs which is good for my height as I'm quite tall)
You aren't just gunna change overnight. The first thing I did was tracked the junk I ate in order to determine my average calorie intake. Then I lowered my calorie intake, it was still big but baby steps right, and still ate the same type of food. Also I forgot to mention even before that I had to learn to eat only 3 times a day with maybe 1 or 2 snacks. So even if you even a bunch of food anyways, at least you are learning good habits by not snacking constantly when you're not even hungry. You might be a bit hungry for the first week but after that your stomach has decreased in size and you won't feel as hungry and you'll find yourself eating less junk. I didn't drink anything carbonated as well so my stomach wouldn't bloat.
So after I was able to stick to say 3000 calories a day by still eating junk food, you have two options here, you can either try eating healthier food but literally try to reach 3000 calories haha, you'll find eventually you're eating less and need less to feel full. Or you can eat the same food and decrease your calorie intake.
After this you should feel A LOT more confidence in your ability to control your food because you've shown yourself you can follow a schedule and have discipline. Drink lots of water too. Try for 2 liters a day and increase if you can (not too much though or your cells will explode lol). After this I was able to start slowly exercising and eventually got to 1500 calories and was exercising 5 days a week, only 45 min a day but that's all you need if you're getting your heartrate up. I did Keto as well eventually, I found it good for seeing immediate weight loss results that boost your confidence to exercise and eat better, but it isn't maintainable I don't think. Carbs are everywhere, I can't help myself haha.
Also, you could start by just cutting out sugar!
Sorry for the long post ;) Hope I helped in any way.