Just installed the Eufy Floodlight and had problems connecting to wifi and also a tip if you’re replacing an old floodlight.
I have Google Wifi that connects devices automatically to the optimal bandwith, 2.4 or 5.0 ghz. Note that Eufy Floodlights only connects to 2.4ghz wifi band. Installation kept failing to connect to wifi. I found an answer somewhere on this forum, that turning off your cell data may sole the problem, which it did.
After that the installation was pretty simple. I would recommend taking a picture of the wire connections of your old floodlight prior to disconnecting it.