WiFi Extenders and Ethernet Cables: How to Choose

Usually no: a wireless range extender links to the router over Wi-Fi. Ethernet is optional on models with a port, and some models can use a wired connection in access point mode.

Ethernet is usually the more predictable link when you can run a cable. A Wi-Fi booster is easier where cabling is impractical, but it needs a good wireless signal from the router.

Yes, if the extender has an Ethernet port and its manual supports that mode. Check whether the port provides a wired client connection or supports access point operation.

It can improve the connection in a weak-coverage area, but it cannot increase the speed supplied by your internet plan and may reduce throughput on a wireless link.