My only life goal

I only have one life goal, and that is to make it to space. I am planning on applying for the ESA, however, I am extremely anxious of how I will set off with this. First of all I need a master's degree in a variety of different subjects (the one I have my eye set on is medicine). Preferably, as well, I need to be an experimental test pilot. However, flight school is extremely expensive. I have thought about joining the French Army but there's a lot of issues with that for me. I need to be extremely flexible and handle mental strain extremely well, which I also need to work on. My most important special interest to me since I was extremely young was and is still space. At this rate my special interest is the only thing that drives me forward. I will only die easy knowing I made it to space. Any advice for seeking out dreams?