What should I do as a self-taught artist in order to create a good portfolio for design college?

Hello! I'm student who just recently finished 12th grade. I will be doing engineering in Computer science for the next 4 years, but after that, I'm interested in taking up design, probably do masters. The thing is, I'm a beginner self-taught artist, I usually do digital art using procreate, however I'm weak in concepts like anatomy, color theory, etc. I will be taking up some online courses and practice it, but I still do need guidance. Also, I know design has various branches, I'm very interested in the fi