Hubs don't do modem only. You would need a VDSL router or a separate modem with the Asus you picked for things to work properly. Either a DrayTek Vigor 130 or a Netgear DM200. The DM 200 is a limited capability router though it can be used as a modem only. You might still get a used Openreach modem from ebay.
You can do that if you like but you end up with double NAT and the associated issues that will cause. Then you basically end up using a perfectly good router as an access point.