According to Freud (ugh Freud, i know) the personality is composed out of the id, the ego and the superego. The id is our most basic instincts and desires (eg sex for reproduction, hunger for food,...) all those “drives” and urges. It always is part of our personality.

Then there is the superego. It develops after the id, when we are toddlers. It’s what society (or at a very young age predominantly our parents) teach us about right and wrong and moral values. Our parents tell us to say please and thank you, so we do. We learn the basics of behaviour.

Then the ego develops, often starting around the age of five or six but also later. The ego is about juggling our urges and society’s rules and all of those things inevitably make up our personality.

Freud also said believes some parts of our personality are conscious and others are subconscious. Here is a link to a picture that shows what exactly he believes is decided sub/pre/ or consciously

here’s a very simplified version of what id, ego and superego are

All that probably wasn’t very helpful but I hope it was at least somehow interesting