Answer
You get a certificate for every vaccination. You can also get a certificate of recovery (infection confirmed with a PCR test or a rapid antigen test). You can find out how to get a certificate of recovery on the page Where and how to get a COVID certificate.
Please note:
Under EU requirements for COVID certificates, certificates of vaccination can only be issued on the basis of a vaccination. Certificates of recovery can only document recovery from coronavirus. Vaccination and recovery are documented on separate certificates.