The first thing you’ll need to do to install a public key is to obtain one. You can download one of our public keys for test purposes by clicking here.
Once it is downloaded, in Kleopatra click File > Import Certificate, and select the file you just downloaded.
If there are no problems with the certificate, you will see a message like this indicating that the certificate was imported.
In your “Imported Certificates” tab, you will also see the certificate now. Once it is imported, you can now use that certificate to encrypt messages.