Really appreciate that you started walk and exercises. Please continue with it.
Regarding diet following rules you follow,
1. Set small realistic targets for every month.
2. Have three meals breakfast, lunch and dinner. Take less of cereals and more of protein sources, salads and buttermilk.
Protein sources include dals, sambhar, sprouts, pulses, milk products like paneer, and buttermilk, egg whites, fish and chicken. Make sure that you take minimum one or two protein sources in every meal.
3. If hungry in between take fruits, salads, egg whites or green tea.
4. Avoid
sugar, sweets, fried, junk, bakery, chocolates, ice creams.
If you crave for this thing eat only once on achieving the monthly targets.