Advice On Divorce And Child Custody

I need some advice for a friend who is planning to file for a divorce from his wife. Their marriage cannot be saved but the wife is not willing to file for divorce by mutual consent only to make his life difficult. They have a 6-month-old baby and she uses the baby as leverage against him. She keeps threatening him that she will not let him meet his daughter ever in life. So I have the following queries : How can he file for divorce? Is it necessary to stay separately for one year before filing for divorce? If yes, is there any loophole that can be used to his advantage as he wants to start with the divorce proceedings immediately. Another important query is after he files for divorce, can a court order be procured at the same time that allows him access to his child till final court judgment as he fears that as soon as he files for divorce, his wife will take away the daughter and will not let him meet her at all. Please help me with these queries. Desperate for advice before going ahead with it.