I’m not sure if there is but it’s just basically joining the string “https://api.qrserver.com/v1/create-qr-code/?size=150x150&data=” with whatever unique value you want. So you can use the join block in the Text drawer to join that string with the green userId block explained here: https://docs.thunkable.com/v/snap-to-place/sign-in-1.
You’ll need to learn about Web APIs and Thunkable if you’re not familiar. I explain a lot of that – probably much more than you need – here: API JSON Tutorial (Video).