Go to this document https://nsrc.org/workshops/2017/renu-nsrc-cns/networking/cns/en/Labs/exercise-pgp-encryption.htm Do all the exercises and copy-paste your screen shots into a Word document and...

1. Install GnuPG (aka PGP/GPG)
2. Generate a Public/Private key pair

You are then asked to enter a passphrase to protect your key:

You will be asked to enter the passphrase twice.

You can see the files containing these files like this:
This will show you a list of keys. You will notice that you have not only one
public/private key pair, but also have a so-called "sub" keys.
3. Encrypt with GPG using public key
It's time to encrypt files...