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 is His slave and Messenger.
First of all, may Allaah reward you for being keen on staying steadfast on the Religion of Allaah and for being keen to be kind and dutiful to your parents.
Indeed, the father has a great status in Islam, and whenever it is possible for a child to obey him in what is permissible without him [child] being harmed, then he should do so. For more benefit, please refer to Fataawa 87019 and 82254.
As regards wearing a beard, then according to the most preponderant opinion of the scholars it is an obligation; for more benefit, please refer to Fatwa 84474 . Therefore, if he orders you to shave your beard or to trim it, you should not obey him because there is no obedience to a creature in disobeying the Creator.
With regard to obeying the father in watching TV, if it is in regard to a matter where Allaah is disobeyed, like listening to music or watching forbidden pictures and so forth, then there is no obedience to him. However, if watching TV is in a lawful matter and the father has an acceptable purpose, then you should obey him. The same thing applies to the prayer, if he forbids you from extending the prayer, for example, for his need for you to help him, then obeying him becomes an obligation as long as this does not contradict tranquility and humbleness in the prayer. However, if he has no acceptable purpose, then there is no obedience to him because this matter is just following one’s desires and preventing people from doing good without a sound reason.
The scholars stated some conditions when it becomes an obligation to obey one’s parents and these are summarized as follows:
1- It should not be in disobedience.
2- They should have a sound reason for doing so.
3- The son [or daughter] should not be harmed by what his/her parents order him/her to do.
A group of scholars stated this, among whom was Ibn Taymiyyah .
In regard to marriage, please refer to Fataawa 120515, 83393 and 92731.
Finally, we advise you to be kind and wise in dealing with your father.
Allaah Knows best.