Looking for something I can plug into my ISP router that acts as another HotSpot that can provide me 2 DNS Servers separate to my Router entirely?

Hey guys,

I'm not really Tech Savy in my old age! However I have an Apple TV and it only allows 1 DNS Server to be added. Ideally I need 2.

I'm using a Smart DNS Server to access Geo-Restricted content. However I need my normal router to use my regular ISP DNS Servers. Is there anyway I can buy another Device that can plug into my Routers LAN port to offer me a total different HotSpot for my Apple TV seperate to my ISP Router and that I can add the 2 Smart DNS Servers to it?

Sorry if this is a little confusing. Any help is appreciated.