Install gpa by entering the following commands in the terminal:
sudo apt update sudo apt install gpa
Description:
GNU Privacy Assistant (GPA)
The GNU Privacy Assistant (GPA) is a graphical user interface for the GNU Privacy Guard (GnuPG). It can be used to encrypt, decrypt, and sign files, to verify signatures and to manage the private and public keys.
Homepage: https://gnupg.org/software/gpa/index.html
Version: 0.9.10-3
Section: universe/utils