All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
There is no doubt that the priority is for Hajj if your father had not performed his obligatory Hajj because Hajj is one of the pillars of Islam whereas the ‘Aqeeqah is desirable and not an obligation according to the view of the majority of the scholars . For more benefit, please refer to Fataawa 89873 and 85682.
Even according to the view that the ‘Aqeeqah is an obligation, then Hajj is a more confirmed obligation than the ‘Aqeeqah.
In addition to this, it is permissible for adult children to perform the ‘Aqeeqah for themselves if their father had not done so.
The Fiqh Encyclopedia reads: “If a child has reached puberty while no one had performed the ‘Aqeeqah for him, then it is desirable for him to perform ‘Aqeeqah for his own self according to the Shaafi’i School of jurisprudence.”
Allaah Knows best.