If you're opening an Excel file and it is unreadable with commas separating information, you'll need to modify your file.
Open the file with Excel.
Click the column header button to highlight Column A where all the data is.
Go to Data menu, click ”text to columns”
Check the box for ”comma” then click Finish.
This should separate the data into separate columns that you should be able to manage in Excel.
Click File -> Save As and make sure to save the file as a .csv or .xls document.