https://en.wikipedia.org/wiki/Brothers_of_Jesus
A good overview of the various positions. You might read and then compare the scriptures themselves. However, if you put tradition and church teaching above the scriptures, do not bother, because you won’t change your mind until the Pope does.
Thank you for posting this link. What it shows to me is that Scripture is ambiguous as to whether Jesus had brothers and/or sisters. Scripture does not say whether Mary did or did not remain a virgin after the birth of Jesus. Scripture does not say whether Joseph and Mary did or did not have relations after the birth of Jesus. Nowhere does Scripture say whether Mary did or did not conceive any children other than Jesus. Neither does Scripture say whether Mary did or did not give birth to any children other than Jesus.
Accordingly, from Scripture alone, it cannot be definitively stated that Mary did or did not remain a virgin. So how did this idea come about? Why was it important to the early Christians that Mary remain a virgin. One possibility is that they felt it was essential because it fulfilled the following Old Testament prophecy from Ezekiel 44:2, Then said the Lord unto me; This gate shall be shut, it shall not be opened, and no man shall enter in by it; because the Lord, the God of Israel, hath entered in by it, therefore it shall be shut. In his Exposition of the Old Testamant, John Gill wrote:
“Some of the ancients have interpreted it of the Virgin Mary, by whom Christ came into this world in human nature, being born of her, a virgin, who had never known man, and as is thought never did after the birth of Christ; nor were any afterwards born of her; no man might come into the world by her, by that self-same way the incarnate God did, and for that reason. This sense is approved of, not only by Papists, but by many Protestant writers.”
https://www.studylight.org/commentaries/geb/view.cgi?bk=25&ch=44#2