megared17B

Safe from what? Safe FOR what?

Wireless bridge it what you want.

It connects as a “client” to a wifi AP, and then has Ethernet ports for your router and other devices to connect to.

And sure, you could setup a raspberry pi to do that, or you could just get a commercially made one.

Most “travel routers” have such a function built in.

Many open source router firmware does too.

There are also devices made that are inherently designed with that as their primary functions.

The only advice I offer is to hire a licensed electrician before you electrocute yourself and/or set your home on fire.