Is it true that God does not forgive someone who tells his friends about a sin he committed, which God had concealed?

Allah Almighty forgives all sins. Minor sins are expiated by performing good deeds and avoiding major sins. As for major sins, they require sincere repentance or the execution of the prescribed legal punishment (hadd). Whoever dies upon their sins without committing shirk (associating partners with Allah) is under Allah's will. However, shirk is not forgiven by Allah. It is not permissible to despair of Allah's mercy, just as it is forbidden to openly declare one's sins, because it is considered a major sin and an act of spreading immorality. It is recommended to sincerely repent and not to openly declare one's sins, and to be mindful of Allah's greatness, seek His forgiveness, and ask for guidance.