edit: I am not specifically tied to pgp, I just want an encryption method that uses a public key to decrypt and a private one to encrypt
edit: I am not specifically tied to pgp, I just want an encryption method that uses a public key to decrypt and a private one to encrypt
GPG is probably the most commonly used one. If you want something with a slightly less awkward command line interface, you could try sequoia-pgp.
Kleopatra for a gui
Alternatively there is also GNU privacy assistant (GPA)