Have just downloaded but the save function fail. After 10 sec nothing happens

All the save options will not work
I have an IMac with the latest versions and lots of memory left.

The Calc, Presentation and Draw can not save either and the drop and pick not either. I have the OS10.15 version.

Drop worked now

Your question has confused me. Please explain what it is that you downloaded. A document, or LibreOffice, or what? And which version of LibreOffice are you using? Please add these details by editing your question above.