Computer science turned bioinformatitian and AI engineer here. I have a BSc in Computer science since 2002 in 2013 I decided to start a Master in Bioinformatics and Computational biology and in 2018 did a PhD. Since my background is in CompSci, first before I started the master I just bought some popular science books about genetics, and biology the kind of books you see in bookstores like Barnes & Nobles, nothing too specialized. Then watched some videos about some things like Biochemistry, Genetics, DNA replication etc... then what really made a difference is taking a Mollecular Biology course, the one I took prepared me with all the pre-requisites and the book I used in the course are these : Essencial cell biology https://wwnorton.com/books/9781324033356

I feel that this book is clearly written and will give you all prerequisites to continue in a biotech, bioinformatics, computational biology or even biology graduate program if you come from a different discipline.

Good luck!