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/

Can anyone comment on how close we are to having Shor's algorithm on a quantum computer? Is feasible like the moon landing was in 1962 when Kennedy announced that "We choose to go to the Moon" (hard, but possible with a lot of money).

Or is it still something that we have no clue how to get to?

Most people consider cryptography as a "solved" problem, but I don't think it is. I am sure if enough cryptologists try algorithmic methods and are well compensated for it, they will likely find algorithmic weaknesses (and invent new kinds of mathematics) that can bring down complexity of solving such schemes, even before we have real and functional Shor machines.