I think you would benefit from some LrC (desktop-classic version) education.
This section on the Adobe webpage in particular is important: https://helpx.adobe.com/lightroom-classic/help/workspace-basics.html. It can also be helpful to read the other sections. Learning how to use the program will help to stop the issues you are having.
As for the originals, look in your desktop folder (outside of LrC) to see if the originals are there. It's possible you simply unlinked the original from LrC.
This section on the Adobe webpage in particular is important: https://helpx.adobe.com/lightroom-classic/help/workspace-basics.html. It can also be helpful to read the other sections. Learning how to use the program will help to stop the issues you are having.
As for the originals, look in your desktop folder (outside of LrC) to see if the originals are there. It's possible you simply unlinked the original from LrC.