[Android Central Question]

Every time I try to connect to the WiFi it says "unfortunately the captive portal login has stopped" and now even the apps are not opening

[Tim1954]

Try a cache partition wipe to start with

[Rukbat]

Forget that Wifi connection, that set it up again. Evidently you connected to a Wifi router using a sign-in page (a captive portal) with the same name as your router is using (most people don't change the default name of the router, and that's how the phone identifies the connection, so not giving your router a distinct name [SSID] causes a problem). If you forget the connection, the phone won't know to look for a sigh-in landing page for a connection with that name.

(If the Wifi signal you're connecting to is a system with a login landing page, then it's not a problem with the phone, it's a problem with the router.)