Dua for new muslim convert
Tariq bin Ashyam (May Allah be pleased with him) reported:
Whenever a man entered the fold of Islam, the Prophet Sallallahu ‘alaihi wa sallam would show him how to perform Salat and then direct him to supplicate:
“Allahumm-aghfir li, warhamni, wa-hdini, wa ‘afini, warzuqni (O Allah! Forgive me, have mercy on me, guide me, guard me against harm and provide me with sustenance and salvation).”‘ [Muslim].
In another narration Tariq said: A man came to the Prophet Sallallahu ‘alaihi wa sallam and said to him: “O Messenger of Allah! What shall I say if I want to pray to my Rubb?”
He said, “Say: ‘Allahumma-ghfir li, warhamni, wa ‘afini, warzuqni (O Allah! Forgive me, have mercy on me, protect me and provide me with sustenance).’ Surely, this supplication is better for you in this life and in the Hereafter.”
Sunnah.com reference : Book 17, Hadith 5
Arabic/English book reference : Book 17, Hadith 1469