1. This was one of my favorite intro to category theory books, will make you familiar with the general language http://math.mit.edu/~dspivak/teaching/sp18/7Sketches.pdf

2. After skimming 1, check out Algebra Chapter 0 which uses Category Theory and diagrams to prove various theorems from Abstract Algebra (Hard read) https://www.amazon.com/Algebra-Chapter-Graduate-Studies-Math...