How can I sincerely repent to Allah and remain steadfast in my repentance, considering that I live in an environment that does not encourage religious commitment, and I find it difficult to abandon sins and accustom myself to prayer, in addition to the influence of friends whom my parents do not approve of?

All praise is due to Allah, who has blessed you with the grace of repentance and the perseverance in establishing prayer after you were among the heedless. The conditions of repentance must be fulfilled, and faith must be preserved, by adhering to righteous companionship and by being gentle with your parents and convincing them of the importance of this companionship. You must also advise your father and siblings to establish prayer.