Over the years I have tried a handful of subfields.

I always felt particularly adept at assembly language programming, so I had a couple projects doing that, and applied to every relevent job I could find.

As a math nerd I enjoyed data science and machine learning, I had quite a few projects like a neutral network from scratch in Matlab, and many data analysis and computer vision projects in R. I was always aware this field is very competitive and my chances were low here.

I had a friend get a job in the biomedical field, so I tried to follow that, I have Python projects doing basic gene sequencing and analysis, even a really cool project that replicated evolution.

Another friend landed a government job, so I followed his advice and got some security certs.

I also had smaller projects and attempts at databases, finance programming, and video games.