Using One time pads - Step by Step

https://www.ciphermachinesandcryptology.com/en/onetimepad.htm

https://github.com/schizolab/one-time-pad-tutorial

https://www.geeksforgeeks.org/implementation-of-vernam-cipher-or-one-time-pad-algorithm/

https://www.tutorialspoint.com/cryptography/cryptography_one_time_pad_cipher.htm