That’s how we do it in my part of the US. And the whole thing is live streamed and audited. My mail ballot is also scanned twice, and I can check if it was received (and signature checks out) and counted. If there’s an issue, I can correct my ballot before election day.
We fill out a paper, but a machine might scan them based on what OP is saying.
Then they will spot check it and have the paper backup if needed.
That’s how we do it in my part of the US. And the whole thing is live streamed and audited. My mail ballot is also scanned twice, and I can check if it was received (and signature checks out) and counted. If there’s an issue, I can correct my ballot before election day.