When I was about 20/21 I thought about enlisting myself to the Portuguese airforce, and once inside, take radio engineering. But I was too late, too old for them, so I took an electronics tec ( level 4) formation, and then I got into cableTv... If I were to "go back" I would like either mechanical engineering or product design.
Why... because even without formal knowledge, I just dive into them whenever I need or can...