Existentialism and Talent

This Friday, Andrew (Mintang Ma), my son took part in the piano competition of the Maricopa Community Colleges and won the first place by playing Ballade No.1 in g minor (Frederic Chopin). I'm so happy and proud of him! He really has the talent of music and playing piano. His teacher in kindergarten found his talent and told me she wanted to teach him playing piano. That's why he began to play piano when he was 4 years old. He is always enjoy playing piano and it seems very easy for him to learn a new piece. So he can keep on practicing for so many years. I'm very grateful for all the teachers that ever taught him. In fact he is also good at STEM study, he wants to go to ASU later.
I do not really understand what existentialism mean.  I don't think man can make yourself be some one just by what you want. I feel every person is different and we all have some  sort of unique talent. Just follow your interests, and work a little hard, then see what will happen. Let nature take its course.