The F4 PRO can only be connected using a 2.4ghz WiFi connection so please make sure you're not trying to connect to a 5ghz connection. If you don't have a 2.4ghz signal set up from your wireless provider it can be requested.
My current recommendation for a home network is to run a 5 / 2.4 GHz main SSID for devices such as phones and computers. Then run a separate 2.4 GHz only IOT network that is configured for Internet access only (no access to local ports). Put your camera, lights, and similar devices on this network. That way you are protected in case somebody has a security hole in their camera or whatever. I use the "guest" network on my routers for my IOT network SSID.
Here is a video of how to install the F4 PRO: https://youtu.be/S4sa7HK9y4s