Error when turning on the PC, what to do?

Question

Windows

I turn on the PC and an error appears Reboot and select proper Boot device or Insert Boot Media in selected Boot device and press a key. In the BIOS, the disk is visible, set as bootable, but it still does not solve the problem, but I don’t want to say goodbye to the disk. What could be the problem?
ASRock UEFI p3.00

Answer 1

First of all, look at SMART and check the disk with something like Victoria, and then according to circumstances.

Answer 2

Replay the chronology of actions.
After what manipulations did this happen.
So you can discard and identify the potential cause of the breakdown.