Talk to Dietitian/Nutritionist on How To Lose Weight

Age 34, male, weight 98kg, height 5' 7/8'', unmarried, patient of metabolic syndrome (blood pressure, cholesterol, pre-diabetes well-controlled with drugs), stress/anxiety (not controlled enough). thyroid profile normal. I think my optimal weight should be 75-78kg as per height. I eat two times a day with 12-hour gap. I eat One roti of whole wheat with salan/curry each time i.e Two roti a day, when there is rice then it is a plate of 200/250gm at maximum. I don't eat dast food, soda drinks, bakery items, sweets, ice-creams, deep-fried foods, food made with white flour/maeda like naan, pizza, schwarma/burgers etc. Only eats a samosa every two month. Dahi Baray one a month. Despite this diet routine not losing any weight, One thing which I lack is exercise/walk which I should have done. But this diet along should have made difference, what do you say? With this diet if I start exercise/walk now, will I be able to to lose 20-23kg ?weight? How much time would it take & what type/durat