Actually beliefs are relieved when God Himself is manifest in you as He was in Jesus. Until that happens in you then all that you have is speculation about a god, a belief about Him with no reality of. But when He is manifest and you actually see Him as He is ye shall be like Him. 1 John 3.“I now realize how true it is that God does not show favoritism 35 but accepts from every nation the one who fears him and does what is right. 36 You know the message God sent to the people of Israel, announcing the good news of peace through Jesus Christ, who is Lord of all."
The Holy Spirit came on all who heard the word. Acts 10:35-44
So belief comes by hearing the word of Christ.