Windows and macOS don't always open .rar files natively like they do with .zip files. You will likely need a specific tool to "extract" the contents:
Once the download is complete, it is always a good idea to scan the file before opening it: Download TARIIIK rar
Many .rar files are password-protected by the uploader. Check the page where you found the link; usually, the password is listed nearby (often the name of the website or a simple "123"). Windows and macOS don't always open