There are 3 main things; PGP owned by a company, OpenPGP, and GPG. Functionally, they behave nearly identical from my understanding. I'll use the term PGP in this post.
It is super easy to use. I'll start with what PGP is or does not:
So, it does NOT do those things. What does it do? It allows for the encryption of text/files. These instructions should work universally.
One might get prompted to create a key-pair right off the bat, which is fine; however, if one is a freedom fighter, on the run from a global government or something 👽, one should ponder if they should put their real information.
"Oh no! How do I get my public key?" Generally speaking, there is an export option somewhere. Don't export the secret key. Make sure the export file begins and ends with 'PUBLIC KEY'. Make sure a key-pair has been created first though.
If one desires, one can send a 'test' message to me. Be sure to include: Your public key so I can send you a message back. I will assume your perferred email address is the one on the public key unless you tell me otherwise.
[1]Keys you get can be... not who you think it is. One ought to verify the truthfulness of where one gets a key. Any key from the internet CAN be the NSA pretending to be somebody. Further reading on this topic maybe needed for those that are security/privacy orientated.