Congratulations on your weight loss. I am going to state the obvious here for you... Exercise and physical activity are not necessary components for losing weight. But those who are not physically active tend to fare much worse as the years pile on.
My wife, who is in her mind 60s was pudgy in high school, but was very active even then. She lost the weight in her 20s and has kept it off ever since and has always stayed very active. Her younger sister was thin up until her 40s but never very physically active now looks much older than my wife. More importantlty, we had to buy a wheelchair for my wife to push her around in When she came up to visit. There is nothing really wrong with her, but she can't get up a flight of stairs without help or even walk around the mall because she is so out of shape.
If you cut your calories, or play some type of metabolic trick on your digestive system by eating only fat and protein... you will definitely lose weight. But if you do not stay active or exercise the years will not be your friend; your quality of life as you get older will not be as good as it could have been. It is the difference between 90 year olds who are still getting around, enjoying themselves and living independently, and 70 year olds who are housebound or sitting in a wheelchair playing bingo in a nursing home. Which future do you envision for yourself?
I was never very active. How ever I did play sport in Junior High and the first 2 years High school.. I wanted a car to drive and my father said either play sports and no car or go to work and have a car. So I went to work and got me a car and a girl friend! On the weight loss thing If you really want to lose weight you can. I lost 95 lbs in 3 months. Simple diet salad.. We’re talking big salads med cheddar, meat on top lettuce tomato and Thousand island dressing. Only ate one meal a day.. around noon.. drank coffee no sugar..