How to add fallover internet redundancy to ST?

I have cable internet at home by which ST is connected over wifi. I want to add rocket stick wireless internet also as redundancy if cable internet goes down than ST is connected over wireless internet…hope I explained my question

The best way to do this is to get a router that supports multiple WAN links and has redundancy functionality, that way it should be transparent to ST (and everything else on your network) which is the way you want it.

Ubiquiti is a popular company for routers that can do this however, they can be a little advanced for some.