How was Buddha meant to be born out of his mother's side?

Maybe it meant he was born with a cesarean….

I don’t know it might be some alien type shit thier is no telling what those ancients actually seen.

It’s allegorical-symbolic and would be specific to the people of the time and place that this Buddha appeared. Additionally, she became pregnant when she dreamed that an elephant, obviously a sacred creature, walked through her stomach area and not through a sexual act, i.e., an immaculate conception.
What does it mean? That the Buddha, like all universal, divine educators — Krishna, Moses, Zoroaster, Buddha, Christ, Muhammad, The Bab, and Baha’u’llah (all “incarnations” of the other) — although physically born are in reality born of one substance, sacred and holy, and are unlike other humans and have a unique purpose, knowledge, and powers — to guide humanity spiritually, intellectually, and socially to the next level of unity and advancement.

Perhaps you are referring to the dream that Queen Maya, Buddha’s mother, had in which a white elephant struck her on her side.

It had something to do Indian Astrology, that all classes of human derive from part of Brahman (supreme being).
Brahmin (Priests class) from head, and Kshatriya (Ruling Classes) from Chest (Rib), Vaishya (traders) from waist, Shudra (laborers) from Knees, and Dalit from the feet etc., etc…
I have also read a similar comparison, in a very old Chinese astrological system.
I think it was metaphorical speaking of his status, as the son of a ruling class- the King.

Greetings,
I think the best way to describe it is that it’s similar to the virgin birth of Jesus Christ. However, the Buddha’s birth is supposed to be symbolic, not literal – it’s a symbol of purity and that a great figure was about to come into the world. Bear in mind the astrologer who came to Siddhartha’s parents and said that the child was either to be a great ruler of kingdoms or a Buddha.
Just a symbolic story matching the symbols of the place and time. I hope this helped, take care.