Open an app with which you can create documents, then click New Document in the Open dialog, or choose File > New.
For example, open TextEdit to create a plain text, rich text, or HTML document.
Apple provides several apps that you can use to create spreadsheets, presentations, reports, and more:
Numbers: Create spreadsheets to organize and present your data. Start with a template, then modify it however you like—add formulas, charts, images, and more.
Keynote: Create compelling presentations with images, media, charts, slide animations, and more.
Pages: Create letters, reports, flyers, posters, and more. This word processing app includes many templates that make it easy to create beautiful documents.
If you don’t have Numbers, Keynote, or Pages on your Mac, they’re available from the App Store.
They’re also available for your iOS devices (from the App Store) and on iCloud.com.