Cannot change DNS in Virgin Media Hub 3

In Zero Trust - Gateway - DNS Locations - Setup instructions - IPV4 & IPv6. It tells me to log on to my router, go to the DNS settings and change them to the IPv4 & IPv6 addresses provided. My Router/Modem, a Virgin Media Hub has no DNS settings to change, Googling “How To Change DNS Settings In a Virgin Media V3 Hub” brings up a page telling me that its not possible to make my changes. My question is, what do I do now then?

Information found in the Virgin Media Community indicates that you will need to provide your own router for use behind the Virgin Media Hub and switch the existing device into bridged modem mode.