I am unable to connect to Wi-Fi on my iPhone 12 Pro Max

Please test the phone using another Wi-Fi network at the coffee place, bookstore, etc.

Can the phone connect to the Wi-Fi network there?

If yes, this tells you that Wi-Fi is working on the phone.....and the issue is with your network Wi-Fi connection. We'll have to work through a troubleshooting process to find the culprit.

If no, go back to the Home Screen. Tap Settings, then tap Wi-Fi. Is Wi-Fi "grayed out"?

If yes, go back to the Home Screen. Tap Settings, then tap Bluetooth. Is Bluetooth "grayed out"?