I’m trying to connect to cox hotspot WiFi on my MacBook but the browser pops up blank so I can’t type in the password

Instead of joining it from the list, click the WiFi icon at the top, and click join other network. Fill in everything as needed. Before I went through network diagnostics and all of that stuff in system preferences, and then I tried the "Join Other Network" method, and now it works like a dream.

Type in a url in the browser address bar and try to navigate to it. This may force the captive login screen to open.