I do not really know how to ask this question but I feel like I must. I have ADHD and am interested in science but do not really know which part of science I prefer. I feel as if I like the connections between ideas more than the ideas themselves. Because of this I feel that I have a bunch of elementary concepts floating around in my head but I have no idea what to do with them (I'm mediocre at a bunch of basic things).

I have been reading through Euler's "elements of algebra" and feel like I am understanding a bit of it until I reached the section titled "containing the analysis of indeterminate quantities", which I am now realizing is known as elementary number theory. The first chapter (of the resolution of equations of the first degree, which contain more than one unknown quantity) has completely stumped me conceptually but I can solve some of the problems (I still feel like I am missing something with them though). What should I feel completely confident in before I tackle the remaining parts of this book?

Any advice is appreciated and I will try to answer any questions. Thank you in advance