What are the requirement of fasting in Ramadan?

There are no requirements. There is only that during the month of Ramadan, you cannot hear music or anything that may give a Muslim sins, look at anything wrong for example tv, you cannot perform anything that is forbidden in Islam or that the shaytan might do. By the way, during the month of Ramadan the devils or shaytans are held in chains by Allah so anything that you do comes from inside you. It is something you desired to do.