Can you explain why safari no longer works on my phone?

Perhaps only after the system version your Safari was

shipped ~ could better be explained with eloquence.

..Check the system settings to be sure they are correct..

All iOS versions have some root cause if they fail to connect.

• Browse the web using Safari on iPhone - Apple Support

https://support.apple.com/guide/iphone/browse-the-web-iph1fbef4daa/ios

• Clear the history and cookies from Safari on your iPhone - Apple Support

https://support.apple.com/en-us/HT201265

• Turn Private Browsing on -or off- on your iPhone or iPod - Apple Support

https://support.apphttps://support.apple

• 19 Hidden Tricks Inside Apple's Safari Browser | PCMag

https://www.pcmag.com/how-to/how-to-use-and-customize-safari-on-your-iphone-or-ipad

• If your iPhone, iPad, or iPod touch won't connect to a Wi-Fi network - Apple Support

https://support.apple.com/en-us/HT204051

• If you need help with your Wi-Fi password - Apple Support

https://support.apple.com/en-us/HT204070

• Use 'captive Wi-Fi networks' on your iPhone, iPad, or iPod touch - Apple Support

https://support.apple.com/en-us/HT204497

https://duckduckgo.com/?q=safari+troubleshooting+iOS+for+iPhone&t=ffab&ia=web

(You may need to consider 'shutdown' and 'restart' of iPhone to see if that helps.)