The fibre connection will be configured as the primary connection on the MikroTik router.
The wireless connection will be configured as the backup connection on the MikroTik router.

The MikroTik router will continuously monitor the status of the fibre connection.
If the fibre connection experiences a drop in connectivity, the router will automatically reroute all internet traffic through the wireless connection.

Please note that the wireless connection will exclusively serve as a backup for the fibre connection and will not be used simultaneously with the fibre connection as long as the fibre connection is online.