Hi there! I understand you're having trouble loading the entire Quizlet website on your Mac running OS X 10.15.7. I'd like to help get this sorted out for you. To start, can you tell me if the issue happens in all browsers or just one? Also, are you accessing Quizlet from home, school, or work? Sometimes network restrictions can cause problems.

In the meantime, let's try a few steps to troubleshoot this:

1. Check Your Internet Connection: Make sure your internet is working properly by trying to load other websites.
2. Clear Browser Cache and Cookies: Sometimes old data can prevent pages from loading correctly. You can clear these in your browser’s settings.
3. Try a Different Browser: If you’re using Safari, try Chrome or Firefox to see if the issue persists.
4. Check for Browser Updates: Make sure your browser is up to date to avoid compatibility issues.
5. Disable VPN or Proxy: If you’re using a VPN or proxy, try disabling it temporarily to see if that helps.

If you are on a school or work network, sometimes Quizlet might be blocked by network policies, which could also prevent the site from loading.

Let me know what you find after trying those, and we'll dig deeper if needed!