Some routers support an Ethernet 'access point' or 'bridge' mode, where you can connect your old router to your main one via Ethernet, and then set up a second Wi-Fi network using that Ethernet ...

Trying to decide whether a mesh router or a Wi-Fi extender is better for you? These are my results after testing both.

She’s had WiFi for the past year and my extender has always picked up the signal no problem. Up until a week ago when she got a new router. So my question is, how do I reconnect my extender?

The extender picks up the signal from your main router and rebroadcasts it, thereby extending the Wi-Fi range. There are a couple of ways to set up your old router as a Wi-Fi extender.