Need advice on where to start

Hi, I m 5ft5 for 191 pounds. At 40 years old, female, I am currently at my heaviest and I seriously need to lose weight. However, I live far from towns and I hate driving ( no buses where I live). I also work around 60 to 70 hours a week. So I would like to do some exercises at home to get me started. I suffer from a lung condition that makes me breathless very quickly but I also know that it can get better if I get fitter. I also suffer from chronic back pain that limits my movements but it might get better once I lose a few stones. I have a mechanical treadmill and I have started doing 5 minutes for warm up and I am hoping to increase this as soon as the breath allows it. I then do some dance cardio that focuses on the core for another 6 minutes ( no jumping, I can't do that) and I do what I can do ( but already can do more after the 4th time so I am not totally doomed lol) followed by some stretches ( all videos taken from Youtube). I purchased some tension bands and I do some exercises using a 10 lbs band, again using videos from Youtube. I can feel my arms aching after each time , my legs not so much so I will need to find exercises for that. If I change my diet, should these exercises help me lose weight or am I doing things totally wrong? Talk to GP about it, they do not seem to know much to be honest. I would welcome any tips or advice. I d like to lose about 60-65 pounds so a lot of work to be done but we all have to start somewhere :) Thanks in advance
My friend had some health problems caused by his weight and after showing to health experts, he had suggested to start eating healthier, less oily and ideally homemade foods and prevent sugar, alcohol and to drink green tea for weight loss. Now it’s been 2 months and he has lost 30lbs.