Is it permissible to travel for the purpose of Hijra (emigration) from a country where corruption is widespread and the means of seeking religious knowledge are scarce, to a country where it is easier to practice one's religion, without the permission of the father who refuses the Hijra, knowing that he is elderly and suffers from illnesses that may worsen if he becomes angry?

The ruling on migrating from your country is that it is recommended if you are able to observe the rituals of your religion and do not fear temptation. Obedience to your father is obligatory unless it involves disobedience [to Allah]. However, if you are unable to observe the rituals of your religion, and temptation [to compromise your faith] has materialized or is highly likely to occur in your religion, then you must migrate, even if your father does not grant permission.