About CSV files
CSV stands for 'Comma Separated Values,' so CSV files have a comma between each item of information they contain. Google Calendar supports most CSV formatted files from commonly used calendar applications such as Yahoo! Calendar and Microsoft Outlook.
With the header information above, Google Calendar will recognize the event as an All Day event by default. To add more information to your events, simply add more headers. Possible headers include: Subject, Start Date, Start Time, End Date, End Time, All Day Event, Description, Location, and Private.
To edit a CSV file, first make sure that the file is originally saved with the .csv extension (many text editing applications cannot "Save As..." a CSV, and manually appending the extension does not make it a readable CSV file). An example CSV file might look like this:
Final Exam,05/12/20,07:10:00 PM,05/12/20,10:00:00 PM,False,Two essay questions that will cover topics covered throughout the semester,"Columbia, Schermerhorn 614",True
This event, 'Final Exam,' would then appear on May 12, 2020 from 7:10 PM to 10:00 PM. The location would be 'Columbia, Schermerhorn 614,' the description would be 'Two essay questions that will cover topics covered throughout the semester,' and it would be a private event. Note that if any of your fields have commas in them (location, in the example above), you can include them in your file by making sure to place quotation marks around the text.
Check out this article if you're having trouble importing your CSV file.