If you treat it as a diet it will be just another diet and you will regain the weight. This is a forever concept. Although you can eat anything there are certain foods that just aren’t good for you. Sugar is out. Which means most processed packaged foods are out. If you want to make life easy for yourself then eliminate any food that is grain based. So no bread, pasta, rice, pizza. No cakes, biscuits. No starchy veggies like potatoes.

Eat lots of veggies, some fruit. Fats like cheese, high fat low sugar yogurt, avocadoes are good for you. Eat nuts like almonds, brazil nuts, walnuts.

No food is banned but go to the maintenance section and ask people there what they did and how long they have been maintaining their weight. There will be a common theme pretty much what Ive mentioned.

Good luck it works if you want it to.