you can’t. It needs to be from a place that uses smart health cards. There are several states that use it. Most (if not all?) states require the vaccinations to be reported to the dept. of health, and some, like CA, use the SMART system for digital records. CA does, and I think a few NE States?

I kind of wish they would enable this with CLEAR also - was pretty simple to get that done with my CDC card - seemed to be verified right away. But like Isaid, I feel like UA already has the vaccine proof from when I uploaded earlier this year as part of the incentive they had to do that. Hopefully that is on file for when needed for international travel