I created a file and attempted to transfer it to Google Drive. As is, with pictures and columns it will not properly transfer. I may remove the pictures however, removing the columns destroys the format of the document. It refuses to transfer as designed to Google Drive. Nor did I have an option for saving as a PDF so that I didn't have to worry about it.
Which LibreOffice version are you using?
You can export as PDF from File - Export as PDF.
Set to NEEDINFO.
Change back to UNCONFIRMED after you have provided the version information.
Ok, at some point the pdf icon came back. I do not know why it disappeared. I was able to create pdf docs I could transfer to Google docs at that point. I just updated to the current version and cannot tell you what version would have been in use at that time - but it should have been the most current. You can close this at this time.