Hello, I’m Virginia an independent advisor with 20 years of expertise in fixing my own & friends’ PC problems.
Which Windows 10 build are you running - 1903, 1909, 2004 or 20H2 (Oct 2020)?
When you chose system restore was there an option to load older restore points?
If Bluetooth doesn’t appear under device manager then check further under View>Show hidden devices - if it is listed there then you should be able to uninstall or update the driver.
If your Bluetooth is disabled then do the following to enable it.
Uninstall the device from device manager and restart bluetooth service.
Start > services.msc
Right-click "Bluetooth Support Service."
Choose Automatic.
Go to device manager and right-click on your computer name and click "Scan for hardware changes"
Install the bluetooth device drivers from the manufacturer's website, if any.
I hope this helps.