What is the best path to learn Category theory and Type theory?
Solution 1:
The best introduction to category theory I know for non-mathematics students is Steve Awodey's Category Theory. Developed as an introduction to category theory for philosophy of mathematics students, the author has also used the original lecture notes to teach computer science majors as well. The book is careful,clear, has many examples and exercises and doesn't pour on too much hardcore mathematics. I consider it one of the best books out there for undergraduates on the subject and I think you might find it just what you're looking for.
I used to recommend Adowey all the time for undergraduates. But for mathematics students,to be honest, I'd prefer Harold Simmons' wonderful Introduction to Category Theory. It's beautifully written and pitched at about the same level as Awodey, but it's much more mathematical and contains far more algebra and topology then you might feel comfortable with. You might want to take a look at it, but be warned-it's really pitched at mathematics students.
Solution 2:
You may find Categories for Types more suitable than Awodey or Simmons (perhaps to be followed by reading Awodey).