A general repentance covers them. Allah says: "Whoever does evil or wrongs himself, then seeks Allah's forgiveness, will find Allah Forgiving, Merciful" (Quran 4:110), and in the hadith qudsi Allah says: "O My servants, you sin by night and by day and I forgive all sins, so seek My forgiveness and I will forgive you" — echoing His words, "Indeed, Allah forgives all sins" (Quran 39:53). You are not required to enumerate every sin — the scholars state that what is unknown or forgotten is included under a sincere, comprehensive tawbah, while any specific major sin you do remember should be named and abandoned. A taught supplication for exactly this is: "O Allah, I seek refuge in You from associating anything with You knowingly, and I seek Your forgiveness for what I do not know" (reported by Aḥmad and by al-Bukhārī in al-Adab al-Mufrad; graded authentic by al-Albānī).
Q&A · Repentance & Sin
How do I repent for sins I can't remember, or sins I didn't even realise were sins?
Evidence — the daleel
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.