From the Finder, Control-click the file, then choose Open With > Numbers. If Numbers is the only spreadsheet app on your Mac, you can just double-click the file. From the Numbers for Mac app, choose File > Open, select the file, then click Open. If a file is dimmed, it’s not a compatible format. IWork is Apple's answer to the Microsoft Office suite of programs, only for Mac computers and iOS devices. It consists of Pages (like Word), Numbers (like Excel) and Keynote (like Powerpoint). Some prefer the look and feel of these apps, especially if working across multiple Apple devices. Everyone needs reliable office software, and some of the very best suites are completely free – whatever operating system you use. New Windows 10 PCs come with a trial of Microsoft Office.
https://exceltree.weebly.com/is-there-a-better-program-than-ripit-for-mac.html. Apple has 'Pages' and 'Numbers' which are able to work with, respectively, Word and Excel files. You can purchase and download both from the App Store in your Dock. Both have the ability to export files as Word and Excel if you need to send files to other people who don't have Macs. Each is $20.
Or, you can purchase Microsoft Office for Mac 2011, which contains both Word and Excel. You can purchase and download it from the Microsoft website. It's $120 per computer, or $150 for three computers.