Hi Rlee8235! Thank you for posting here in Apple Support Communities, and congratulations on your new iPhone 12 Pro Max!
We understand that you're experiencing issues with Airdrop and with the ringer volume, and we'd be happy to help. With the ringer volume issue, it actually sounds like this might be related to the Attention Aware features, which is expected to lower the ringer volume when you're looking at your iPhone. For more information, please check out: About Attention Aware features on your iPhone X or iPad Pro
As for Airdrop, we'd like to ask you a few questions and have you try out a few things. Are you looking for a specific device, or any device in general? If the former, are you able to find your new iPhone on that device?
If that other device is an iOS/iPadOS device, let's go into Settings > General > AirDrop off and back on. Please do the same for your new iPhone as well.
If the other device is a Mac computer, please disable the application firewall. Here's how: About the application firewall
We should also check that each device has Wi-Fi and Bluetooth enabled, Personal Hotspot disabled, within Bluetooth range of each other, and both devices are awake.
Confirm that AirDrop is set to Everyone on all devices, and then let's restart those devices.
Once you've done all of the steps above, test to see if you're now able to locate and Airdrop to those other devices.
Cheers!