Hi
I am very much your senior, (72 and male) but I hear you loud and clear.
Let me say, you can do it, and you can do it much faster than you think you can due to your age.
Some years back, a young friend stayed with me to help fix up a house I bought. He was severely overweight and wanted it off so he would be more attractive to girls also. He asked me how he could lose it and if I would help him. I told him I could tell him how and support him, but could do nothing more than that. His parents, especially his dad, ate way too often, and way too much when he did, the kid ate the same way.
I showed him the field next to me and told him it was half a mile long, to run the length and back 3 times a day and eat smaller portions of his food. He did and sliced 30 lbs off in 45 days time. What a difference it made on that 14 year old boy
Your weight is much more, so I would reccomend just walking about 4 miles a day fast, running would be too much stress on your bones even if you can do it. When the weight gets down jogging some could be fit in.
I do not know how to handle the problem with purchasing the sort of health foods you wish, but you can manage smaller portions in some way. Try to stay up with your calorie intake, calculate the required calories that you need to maintain your weight and stay under that. Remember, you do not have to be less every single day, even if you wind up going out with friends and pigging out to an extent. Just resume the lower calorie intake without guilt or remorse and continue on. Many fail to stick with "diets" which consist of foods they do not like and going around being hungry. Learn to eat smaller portions, exercise and how to manage with the foods you do have.
Take what you want of what I say and let the rest go
And the very best to and for you, I want to see you succeed
B F R