M1 Mac mini & iPhone 11 Pro bluetooth pairing

Mac mini 2012 and later are supported.

Bluetooth must be turned on for Continuity Camera but the devices are not Bluetooth paired. See the information in Continuity Camera: Use your iPhone or iPad to scan documents or take a picture on your Mac - Apple Support including the following:

Additional requirements

• Both devices must have both Wi-Fi and Bluetooth turned on.
• Both devices must be signed in with the same Apple ID using two-factor authentication.

If by connect you mean pair, the iPhone an iPad are not designed to pair with each other.

I can't think of any reason for it Continuity Camera not to be working if you've addressed the requirements in Continuity Camera: Use your iPhone or iPad to scan documents or take a picture on your Mac - Apple Support

You may want to contact Apple Support: Contact - Official Apple Support

Other information regarding Bluetooth and continuity:

See the information in: Bluetooth: Why can't I pair my iPhone or … - Apple Community

If you are attempting to use Handoff/Continuity or AirDrop, that does involve Bluetooth but the devices are NOT paired; Bluetooth just needs to be on and the devices in range of each other. The following may help with Handoff/Continuity issues: Use Continuity to connect your Mac, iPhone, iPad, and Apple Watch - Apple Support

Also see Share files between your Mac and Bluetooth devices - Apple Support