Genes are really scary. Why do they even have similar personalities? I think one-third of me is like my dad.

Yes, appearance and personality will affect it. And it has a profound impact.

Personality is a very broad term, which includes innate temperament types and thinking types, which are difficult to change acquired. But the world view, outlook on life, values, and characteristics in dealing with others are completely acquired. As long as you live with your own parents, you will be influenced by them, but if you grow up in someone else's family (such as an adopted child), these aspects will be close to your adoptive parents.