Hi I'm 22 yrs old female my weight is 43 kg how many squats are enough for me and how many reps? Will it help me archive good body and posture?

Malnutrition. Before you use up all our energy and protein building blocks by working out, please improve your nutritional status first. You need all your essential Amino Acids to build good muscles and help with posture, so follow the recommendation i gave to your other question.