I've gained a lot of wheight in the past few years

Did u gain that weight because of meds. Some meds can cause crazy weight gain such as the antipsychotics.

I've had good experience with what's called the 16-8 Diet: very simply, you can eat whatever you want during the same continuous eight-hour period every day, but you can only drink zero-calorie liquids for the other 16 hours.

The "official" diet says the eating hours are between 10 am and 6 pm, but I eat between 12 noon and 8 pm. It took a few weeks for my system to get used to this, but it wasn't long before I simply didn't feel hungry outside those hours. The weight reduction isn't drastic and immediate, but then diets which do that are always doomed to fail.

There is some evidence that giving your body a daily 16 hour break from processing food also helps with diabetes and blood pressure regulation.

https://www.sciencedaily.com/releases/2018/06/180618113038.htm

Our metabolism slows down as we get older so we don't need to eat so much.

Here is an easy diet. Cut way back on carbs like bread pastries potatoes and so on. Eat more fruit and green veggies. Broccoli and kale are two of the best.

Cut out ALL sugar. Sugar metabolizes into glucose very fast. Your body cells need glucose and when the body cells have absorbed all they need the rest gets stored as fat. If you need a sugar substitute use Stevie which is a natural sweetener with no cap like aspartame in it.

I read somewhere that as we age we get a bit shorter and lose some bone mass so you should lose about a pound a year to compensate.

cut that fat off

Stop eating.