All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.

Dr. `Abdul-Fattah `Ashoor, a professor of Qur’anic exegesis and its sciences at Al-Azhar University, explained that

Any illicit relationship one had before getting married according to shar’iah was a sinful one, and both parties have to sincerely repent to Allah. Though according to some Muslim jurists, it is permissible for a Muslim man who has repented from fornication to marry the Muslim woman with whom he was fornicating if she also has repented to Allah.

However, the contract or agreement you made at that time is null and void as it lacked the necessary prerequisite for a shari’ah based marriage, such as the attendance of a wali (guardian) and two just witnesses. If your father is not a Muslim, he cannot be your wali. But if he is a Muslim and is not residing with you, you will need his approval at least. In both cases, a Muslim judge could be your wali.

So, what you have to do is that both of you go to the shari`ah court in your emirate where you can conclude a valid and shari`ah compliant marriage contract.