The PC Gods Were kind to me.  Thank you everyone for your tips and suggestions.  Tried them all and found this one to work.  Listening to some great music on my BT headphones as I type! Fixed My Missing Bluetooth Toggle On Issue  performed a motherboard reset..... 1/ shutdown2/ remove power cord3/ hold power-button for 10secs4/ re-insert power cord and power-on
I am at my wits end!  I can no longer use Bluetooth as the button to turn on Bluetooth on my W10 XPS 8930 is gone.  I have spent a week troubleshooting before I am posting here.  Have tried all of the troubleshooting steps on Dell and on the Internet-only thing I have not done is reinstall W10 or upgrade to W11.  The XPS8930 came with Qualcomm QCA61x4A/QCA9377 Wi-Fi and Bluetooth Driver, and I have the latest one from the Dell Support website for my PC, which is Qualcomm-QCA61x4A-QCA9377-Wi-Fi-and-Bluetooth-Driver_YX23Y_WIN_12.0.0.1118_A47_03.EXE. Have also updated my BIOS to the latest version as well as the Intel Chipset.  I'm pretty sure it's a driver issue as no Bluetooth shows up in Device Manager while the wireless card does show up and works fine. When I run the Dell diagnostic tool it sees the wireless card fine but no indication that Bluetooth is present on the PC. If anyone has experienced this before and has some ideas would greatly appreciate your suggestions. Thank You  Roger
XPS 8930, Bluetooth toggle On/Off button missing Windows 10