The built-in form system allows you to export the data as a CSV file.
To do so, go to Forms > Import/Export > Export Entries and select the form for which you would like to download the CSV.
You can then select the specific fields you would like to export (or all), add a conditional logic if needed (for example export only people named John), and if you want, add a time range for the entries (e.g. only last week’s entries).
To have more information, please read Gravity Forms’ documentation.