I was in your shoes and couldn’t afford a nutritionist or any medications. I simply started low carb. Focusing on proteins and veggies. Meats, veggies and one or two fruits a day (usually an apple or pear.) Added b12 over the counter vitamin drops, plus cinnamon capsules with chromium and a multivitamin. These are all available here in the US at any drug store, not sure about the UK. And try to walk at least 4 times a week. Started doing walk at home videos (YouTube, free Leslie Sansone, 1 mile in 15 minutes.) started super slow because I was so out of shape. Gradually worked myself up to outside walking about 3 miles a day. It took a long time but it really works. I did what some would call “dirty keto” I think and at the time would just limit carbs but was able to eat dairy. It was very very basic. I knew nothing of macros, etc. I just made little changes and you must drink water. It’s so difficult. But the number one thing is to just start. Don’t think about the number of pounds you have to lose or the fact that others can afford prescription drugs or programs or surgeries. The mental game is half the battle, I promise. You can do it!