Gigasheet allows you to export the data in your sheet as a CSV.
Export will export all columns and rows in the current result set. That is to say, it's all rows matching any filters being applied, and all columns marked as visible. In a sheet with a filter applied that shows this row count:
The export will contain those 4,905 rows.
If the filter were removed on the same sheet, and the row count looked like this:
The export would contain all 4,875,679 rows.
For both of these exports, the columns included would be every column marked as visible. Hidden and deleted columns are not part of exports.