Can I import an existing Excel sheet into Libre Base?

My Excel version is 14.0.7153.5000 32 bit Office 2010 and my Libre office is 4.4.52
I have imported my XLXS sheet in Libre Calc successfully.

I’m new to Windows databases. Is there a “Getting Started” text file I can down load?

For usual desktop-size data sets, it really is quite simple. This is the guide I have found most helpful. Open the dataset in Calc, select the cells you would like to export to Base, copy the cells, and then go over to Base, click on the Tables tab, and paste the clipboard, follow the remaining prompts to configure the columns. That is by far the easiest way to do it.

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You can save the spreadsheet from Excel or LO Calc as a csv file ande import it into LO Base.
These articles should help:

Importing and Exporting CSV Files - LibreOffice Help

http://dominoc925.blogspot.com/2013/05/import-csv-file-into-libreoffice-base.html