NO BOOTABLE DEVICE FOUND

My laptop, the Dell Inspiron 7370, was unable to boot up.  I tried multiple times to boot it up and run through the different diagnostic tests to no avail.

When I try to boot up the laptop on its own, I receive the error message "no bootable device found" along with only one option: to shutdown the device.

I then tried to boot up the device through the pre boot system (F12 key).  I then noted that the secure boot mode is on.  I ran the diagnostics and found no errors.  I then ran the "Thorough Test Mode" and also found no errors.  Seeing this, I exited and restarted the laptop under setup mode (F2 key).  I reset the BIOS settings to the default settings and tried to reboot the laptop again (still getting the same error message).

I re-ran the diagnostic tests and the "thorough test mode" under the pre boot system (again with no errors), but am still unable to boot the laptop up correctly. Under the event log and results tab, I see that the tests were passed as well.  I also re-ran the hard drive test but only saw that it passed that test as well, again.

I checked through several online forums and it seems that a hard reset is an option, but because the laptop does not have a removable battery, I am unsure of how to do a hard reset.  

Also according to a Dell online manual, the sounds the laptop makes may be important in diagnostics as well; the computer only beeps once when the tests are passed but makes no other sounds.

Any advice on how to do a hard reset on my laptop or on how to proceed from here would be great!  Thank you!