To open a ZIP file on a MacBook, open Finder and locate the ZIP archive on your computer. Once found, double-click the file and let macOS use Archive Utility to unzip it automatically. No other software is required to open ZIP archives except in some rare cases involving corrupted or password-protected archives. Once unzipped, a new folder/file will be created near the original archive. If the file fails to unzip, make sure the file is downloaded and that it is actually a ZIP file. The file may be corrupt if macOS says it is, and you can download it once more from the website.