Hello and welcome to the forum. We want to commend you for deciding to take your health seriously and wanting to get on track. The issue of losing weight and cleaning up your diet and lifestyle is important and we are glad you are embracing these changes! Normally one should have a physical. Understanding you do not have insurance and during covid, this is a tricky time for healthcare in general, but it would be best advised to get a baseline physical. Many urgent cares may do that or doctors may allow for self pay. And they often have pricing that someone without insurance can work with. This is really worth checking into. You want the go ahead and all clear to begin exercising although you can start on your diet now.
This guide may be helpful. https://www.hsph.harvard.edu/nutritionsource/disease-prevention/diabetes-prevention/preventing-diabetes-full-story/ But essentially, without any blood work, we don't know where you are at with this condition. If it is even a concern or you are already diabetic.
Is there any chance you can find a doctor to be evaluated?
Your condition would really need a doctor's attention. I hope you can find a way to get assistance. Particularly of concern are the cracked feet and sensation problems. IF you have diabetes you may also need medications to help lower blood sugar.
If you have diabetes, you could consider following a low carb / keto diet. After all, diabetes is a condition where your body can no longer handle carbs / glucose. This means no sugars, no grains, no starchy veges, no sweet fruits. You can find much information online if you look for diabetes and keto or diabetes and low carb.
To get enough energy you need to eat more fat (the fat replaces the carbs).. these fats should come from unprocessed foods / meats etc. Your diet would then consist of vegetables (leafy greens, salad veges, avocado), some nuts, and proteins with fats. People following low carb diet typically need to increase salt and electrolytes intake, and drink plenty of water (unsweetened tea, coffee, etc also ok).
It can be hard to follow a low carb diet if you are eating vegan, so you may wish to research.
Again, hope you can find medical help as well. Please let us know how you go.