my iPhone 12pro WiFi greyed out and bluetooth not working

Hello ~ Take a look at this excellent prior post by *Chris_C1* one of our Community Specialist:

“First, make sure that you don't have restrictions set for the iPhone by going to Settings > Screen Time > Content & Privacy Restrictions > Content Restrictions. If Content Restrictions is turned on, then there may be a setting enabled that is preventing Wi-Fi and Bluetooth from being changed. Temporarily toggle off Content Restrictions to see if you're able to turn on Wi-Fi and Bluetooth again. Learn more about Screen Time restrictions here: Use Screen Time to get insights about how you use your device. 

If there are no restrictions set on the device, then try both updating and restarting the iPhone. There are other methods you can use to update the iPhone other than with Wi-Fi:

Restart your iPhone

Update your iPhone, iPad, or iPod touch

If they are still grayed out, Contact Apple Support.”

~Katana-San~

Reset Network Settings: Only network settings are removed.

• When you reset network settings, previously used networks and VPN settings that weren’t installed by a configuration profile or mobile device management (MDM) are removed. Wi-Fi is turned off and then back on, disconnecting you from any network you’re on. The Wi-Fi and Ask to Join Networks settings remain turned on.
• To remove VPN settings installed by a configuration profile, go to Settings > General > Profiles & Device Management, select the configuration profile, then tap Remove Profile. This also removes other settings and accounts provided by the profile. See Install or remove configuration profiles on iPhone in this guide.
• To remove network settings installed by MDM, go to Settings > General > Profiles & Device Management, select the management, then tap Remove Management. This also removes other settings and certificates provided by MDM. See “Mobile device management (MDM)” in the iOS Deployment Reference.
• Reset your Network Settings. Tap Settings > General > Reset > Reset Network Settings. This also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you've used before.

If the above fails....

Go to Settings > General > Reset > Reset All Settings

• What this effectively does is to reset some of your Settings to factory default. It’s not a complete removal of settings. It removes all of your preferences for Wi-Fi, Bluetooth, Do No Disturb, Notifications, General, Sounds, Brightness & Wallpaper and Privacy.
• Resetting all settings also reverts all your personalized and customized features like wallpapers and accessibility settings back to factory defaults.
• Performing this action does not impact any of your personal device data, including photos, videos, notes, messages, reminders, emails, calendars, texts, documents, and other files