If you have Microsoft Word installed on your Mac, you can simply double-click on the.docx file to open it. If you don't have Word, you can download and install it from the Microsoft website. Alternatively, you can also use the Pages app, which is a free word processing app that comes pre-installed on Macs.
Pages is a great option if you don't want to spend money on Microsoft Word, and it's also very easy to use. You can import.docx files into Pages and edit them just like you would in Word. Plus, Pages has a lot of cool features like templates, fonts, and formatting options that make it a pleasure to use.