Ciao Szanecka and welcome to our community. If the booster confirmation you have includes the information required by the Italian government, and you're coming from a country whose certificates are recognized by Italy, then the paper vaccination certificate should be equivalent in Italy to the digital certificate with a QR code (for those with an EU Digital Covid Certificate).
The Italian health ministry21 specifies the following needs to be on a vaccination certificate issued by the competent authorities:
- full name and birthdate;
- trade name of vaccine administered;
- date vaccine was administered;
- identification information for authority issuing certificate (State, health authority).