"Add verifiable COVID-19 vaccination information to Apple Wallet and Health"
I just updated to iOS 15.1 and the Health app detected that I'd received the vaccine and offered to add the proof-of-vaccination card (with barcode) to the Wallet app. One touch and there's a nice, easy to access "card" in Wallet. Nice.
Add verifiable COVID-19 vaccination information to Apple Wallet and Health - Apple Support
Add verifiable COVID-19 vaccination information as a vaccination card in Wallet and download and store verifiable vaccination and test result records in the Health app.