Sins committed before converting to Islam
Islam erases all sins committed prior to becoming a Muslim.
Allah says :
“Say to those who have disbelieved, if they cease (from disbelief), their past will be forgiven. But if they return (thereto), then the examples of those (punished) before them have already preceded (as a warning)”
Amr ibn al-Aas (may Allah be pleased with him) said: When Allah put Islam in my heart, I came to the Prophet (peace and blessings of Allah be upon him) and said: Give me your right hand so that I may swear allegiance to you. He held out his hand and I withdrew my hand. He said, What is the matter, Oh Amr? I said, I want to stipulate a condition. He said, What do you want to stipulate? I said, That I will be forgiven. He said, Do you not know that Islam destroys that which came before it? (narrated by Muslim)
Prophet (may the peace and blessings and mercy of Allah be upon him) said, Islam annuls what came before it. (narrated by Muslim)
So as you become a Muslim all your previous sins are forgiven and you start a blank state. Or a complete clean record