Yes.
Talk about having friends! Thanks a bunch for the quick help!
Yes. Use the same SSID and password for each. The additional access points will extend the wire network (WLAN) to where you place them. My house has been this way for years, including outdoors.
Office buildings and large public spaces are set up this way. Mesh WiFi is a rage now, but there is no need to dump your working access points for that if you have wire in the house.
I turned off the wireless on the network router because I’m an old fart that thinks a router should be a router and an access point should be an access point. It’s in the basement anyway, so would be rather useless as an access point.