First, above all, know that if your child is more reserved or introverted, there is nothing to be “fixed!” In some cases, children might need to work to develop self-confidence and overcome shyness (shyness-rooted in anxiety- is different than introversion), but the reserved child does not automatically need “fixing.” Some children are simply designed this way and need your support and encouragement along the way, especially because culture and society will tell them that something is not right and that they must be “a certain way” to be accepted.
You can check out some more tips here.