cant open word and excel

When you opened that *.xls spreadsheet in LibreOffice 7.1.4, did you perform a Save As using File type Excel 2007-365 (.xlsx) as the output file format to your local drive? Did you choose the following selection when prompted:

I just opened an Excel (.xls) spreadsheet that was created in 2006 using LibreOffice v7.1.4 on macOS 11.4. I saved it to my Desktop as a .xlsx format per the blue selection above, and then opened it without an issue using Numbers v11.1.

As it turns out, I can open the original 2006 Excel spreadsheet directly in Numbers v11.1 too.

I suggest that if your profile is correct, and that you are still running macOS 11.1, that you update to macOS 11.4, because Numbers v11.1 may have code in it that expects the current release of Big Sur.

If your profile is wrong and you are running macOS 11.4, then I suggest booting your Mac into Safe Boot mode, and attempt opening that original .xls spreadsheet with Numbers. If successful, then there is an external reason for Numbers failing in normal boot mode and not really an issue with Numbers itself. Reboot normally, and again, see if you can open that same .xls spreadsheet with Numbers.

With Pages or Numbers open, go to File > Open and navigate to the .docx or .xlsx file you want to open.

If you need to open files in older .doc and .xls formats then you could try downloading a copy of the free LibreOffice, opening the files with that and Save As in a newer format, which you can then open with Pages or Numbers.

SG