Question: Do we decide if we are an introvert or extrovert or is it something with genetic psychology?

Andrew McNeill answered on 20 Mar 2020:

Good question! To some extent the question of introvert vs extrovert is artificial because we behave so differently in different situations. But assuming that some people tend to be more introverted/extroverted, there is evidence that this can change over time (working in retail made me more extroverted, for example). There is also evidence that genetic factors predict introversion/extroversion but genes always interact with the environment so that people with the same genes can be introverted in one environment and extroverted in another.
As to whether we decide on what we are going to be, I think we would agree that you can’t just make a single decision to be introverted or extroverted. But I think that hundreds of small choices about how we live our lives can shape our personalities in significant ways.