What is the ruling on frequent swearing by the Qur’an, and what is the expiation for repeated breaking of an oath due to not committing to study and abandoning the phone, knowing that the one who swore the oath is not financially capable?

This method of striving against oneself by frequent swearing is not legislated, because frequent swearing restricts the Muslim and might expose him to not upholding an oath, which is commanded by the Shari'a. Breaking an oath regarding abandoning the mobile phone or committing to studying is not forbidden, and there is no sin in it, because it is not an oath to perform an obligation or abandon a prohibition. If you break multiple oaths and covenants concerning one thing, a single expiation for an oath is sufficient for all of them. However, if you break an oath and expiate for it, then swear another oath, a second expiation becomes incumbent upon you.