Is it permissible for a Muslim who is gifted in rap singing to sing, given that his songs contain advice and guidance and call to Islam?

Making people love Islam and its teachings is not achieved by disobeying Allah. The prohibition of musical instruments and music is a matter of consensus among the majority of jurists and scholars.

Therefore, it is not permissible for us to disobey Allah in the very act of seeking to invite others to Him. Allah has indeed broadened for people numerous permissible means of da'wah (invitation to Islam), such as dialogues, conferences, lectures, and various events.