Is it obligatory to fund a son who does not pray to study abroad (Canada) in an audiovisual specialization, or to fund him in the same field in Tunisia?

This specialization is often associated with impermissible (haram (definition)) acts in Islamic law. The questioner must assess whether his son will use his studies for prohibited activities. If he strongly believes this to be the case, then he is not permitted to assist him. Instead, he must advise him and keep him away from anything that harms his religion, as Allah Almighty says: "O you who have believed, protect yourselves and your families from a Fire whose fuel is people and stones." (Quran 66:6). More importantly, the issue of his son abandoning prayer should be his primary concern regarding his child.