Thanks for the link.

You can download this entire Handbook of Applied Cryptography for free [1].

Recently the authors also provided online course and video namely:

- Cryptography 101: Building Blocks (fundamental cryptographic primitives) [2]

- Cryptography 101: Real-World Deployments (PKI, TLS, Bluetooth, AWS, Signal) [3]

Other courses and video includes:

- The Mathematics of Lattice-Based Cryptography (introductory course)

- Kyber and Dilithium (standardized lattice-based cryptosystems)

- Hash-based signature schemes (LMS, XMSS, SPHINCS+)

- Error-Correcting Codes (linear, Hamming, Golay, cyclic, BCH, Reed-Solomon codes

[1] Handbook of Applied Cryptography:

https://cacr.uwaterloo.ca/hac/

[2] Crypto 101: Building Blocks:

https://cryptography101.ca/crypto101-building-blocks/

[3] Crypto 101: Real-World Deployments:

https://cryptography101.ca/crypto101-deployments/

I don't remember if it links to it, but this pairs well with https://cryptopals.com/, which are practical examples of many of these theories.