Generate a private key

gpg --gen-key

Export a user key

gpg --export [UID]

Import a key

gpg --import [Filename]

Other samples

gpg --gen-revoke
gpg --list-keys
gpg --fingerprint

Protect your key

gpg --armor --output pubkey.txt --export 'Your Name'

Decrypt a file

cat x1.txt.gpg | gpg -d --output x1.txt