When you go to save your file, if you do a "Save as," the "Save as Type" dropdown list towards the bottom of the Save As winddow allows you to select .csv as a format. This brings up a wizard that self directs you through a process to:
1. Create an import/export map, which can be saved
2. Select the fields you want to export
3. Select Tasks and or Assignments
4. Select an existing filter to limit the tasks / assignments that are exported.
It’s easy to use and works well.
You have 3 options that you can select as a text delimiter between columns – Tab, Space, or a comma ",". Keep in mind that if you use commas in Task Names or text columns, this can be a problem for a .csv export if you are importing into another application.
Use the free download at https://www.mrmikesaddins.com/. Works wonderfully to give formatted results, including a pivot that you can customize to manipulate the data how ever you want in Excel.