How do we know which madhab to follow and is it mandatory to follow?

So if you're unsure, Allah says Ask somebody of knowledge, whoever that person may be, a scholar you trust and go with that view because that scholar would have studied the various views, the various opinions and so on and will be able to then give you a specific ruling. It's the same with any field Let's say for example, heart surgery. You wouldn't just read a book on heart surgery and then choose which way of surgery you think is best You would go to a heart surgeon who has experience and who is trained and qualified and go with their view. So the same for Islam, the same principle If you don't have a specific madhab, then just ask somebody of knowledge, whoever that person may be and go with that view. If you're studying, then I always advise to study a particular madhab when you start because that will provide you with principles and then you can maybe study another madhab or then compare between different madhabs But if you're studying, then always stick with one madhab initially Otherwise it will become very confusing.