U v chance to grow till 21/ but 18 years is the best time to finish . Take good quality protien S like dairy, organic, plant etc. also do some free hand, stretching ,skipping etc.

You need yo do stretching exercises. Have banana daily. What is your weight

Do you have beard and moustache...if yes than probability of gaining height is less and if no...than still you can try for height growth. Low intake of total calories and protein and High intake of sugar, sweets, bakery, junk food is associated with stunting. So take three healthy meals made at home which apart from rice or chapati should include dals, pulses,sprouts, eggs, fruits, veggies, nuts. Milk without sugar three times a day. Bedtime milk helps in gaining height. Cardio exercises like jogging and cycling on daily basis helps to increase height.