With this tool, you can:
Connect your clock to serial and enter flashing mode. That usually means connecting GPIO0 to Ground. Learn how here.
Reset with GPIO0 not grounded and you can set up Wi-fi configuration, visit the device's WebUI, or add to Home Assistant. Then, click 'Connect' again.
If you are having issues seeing the option to setup Wi-fi configuration, try reloading this page. It doesn't matter which firmware is selected to send Wi-fi configuration.
These firmwares likely contain time zones that do not match yours. That's OK, you can change them! For non-HA versions, you can change the POSIX string of the Alternate Time Zone in the device's Web UI. For HA versions, you can override the time zones with Helpers.