What is the ruling on lying to one's father to avoid problems, knowing that the lying is directed only at him, and the young man performs the five daily prayers?

The general rule regarding lying is that it is forbidden, except in specific situations. If you fear that problems will arise with your father, you should use allusions (al-ma'arid) instead of outright lying. If that is not possible, and speaking the truth would cause definite harm while lying would bring a preponderant benefit, then lying is permissible for you. However, if there is no such need, then lying is forbidden, and repentance from it is obligatory, along with striving to accustom oneself to truthfulness.