Don't update to Tahoe Public Beta yet, wait until it's released.

On the beta of Tahoe there is an issue, whenever you update, at first it seems like it's fine, but the second you shutdown / reboot, it's over. FileVault gets enabled whenever you update and multiple users had issues with it: it locks you out completely. I had to reinstall macOS because of this, disabling it isn't possible, even from recovery. It will give out an error. Stay on Sequoia, it's not that long until the release anyway.