1. Open Calc file
  2. Choose File>Open
  3. In the "Files of Type" drop down menu, chhose TextCSV(*.csv;*.txt)
  4. Choose the coorect file and press "Open"
  5. You'll get a window that will have you specify the delimiters (which is usually commas). There are also options to format the data as you want it to show up.
  6. When you are done press "Ok" and the data will be present as a spreadsheet and can now be saved as such.
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