Not a lot of people pay attention to their personality while choosing career but then they end up having a job or a career which they hate.
Hence, it is extremely important to pick a career which suits the best to your personality.
Do you like to talk to a lot of people or do you prefer to be alone ?
Do you like sitting in front of the computer all day or do you like to be in the outdoors?
There are always some personality traits a person has, some likes public speaking, some like spending time alone, some like to travel a lot.
Depending on what your personality trait is, you may choose your career.
Like to travel a lot ? You may choose to be a travel agent or setup a travel company.
Like to stay at home all day and like tech? You can be a freelance developer.
Like engineering but also like to spend time outside and interact with people? You can be a civil engineer.
So, in summary, your personality needs to be understood before you can start anything with yourself.