As written below, "Introduction to Modern Cryptography" by Katz & Lindell. Another option would be "A Graduate Course in Applied Cryptography" by Boneh & Shoup. However, for starting out, I would definitely recommend the former as it's more polished and focuses on the essentials.

I took Boneh's graduate class a few years ago through SCPD. Recommended if you can justify it. He has a Coursera course that I assume is of similar high quality with less depth and rigor.

We used the above two books in addition to Handbook of Applied Cryptography by Alfred J. Menezes, Paul C. van Oorschot and Scott A. Vanstone. I notice Boneh no longer uses the latter for CS255; perhaps it is too out of date now? At any rate, it is also available free on the web: https://cacr.uwaterloo.ca/hac/

Oded Goldreich's "Foundations of Cryptography" books are the rigorous, theoretical oriented books used in many grad-level crypto courses: https://www.wisdom.weizmann.ac.il/~oded/foc-book.html

Neil Koblitz has "A Course in Number Theory and Cryptography", which I haven't read, but is often used: https://www.amazon.com/Course-Number-Cryptography-Graduate-M...

Also, Boneh and Shoup is good and mentioned in other comments: https://toc.cryptobook.us/

Steven Galbraith's Mathematics of Public Key Cryptography: https://www.math.auckland.ac.nz/~sgal018/crypto-book/crypto-...

J. Katz, and Y. Lindell, 2015: Introduction to Modern Cryptography, 2nd ed. CRC Press, 583 pp.

Cryptography: Theory and Practice, Third Edition by Douglas R. Stinson