Modify my Airport Express for new WiFi network?
I have two Airport Express Gen2 with dual band 2.4 and 5 GHz. My Apple Extreme failed so I now have a Netgear Nighthawk router that works great. But, I cannot figure out how to modify the settings on the Airport Express. Using the Airport Utility it shows a legacy image of the Airport Express on the screen but not connected to the wireless internet of course because the network name is no longer valid. I am unable to use the Airport Utility to open the setup window to change this. I put an ethernet cable from my MacBook Pro to the Airport Express in the hopes of communicating in this way. But, the Thunderbolt Ethernet has only a self-assigned IP address. The little "manual" that came with the Airport Express said that I should be able to connect to the Airport Express for setup with an ethernet cable to my Mac but it is helpful no further. All I need to do is to open the setup window somehow on the Airport Express so I can modify the network name to which it should connect. Can anybody provide help?
MacBook Pro 13", macOS 10.15