I just installed Firefox and it won't open common websites like credit cards, even firefox help website because "secure connection failed". What do I need to do?

This message was received when I tried to follow the support link "support.mozilla.com". Secure Connection Failed The page you are trying to view cannot be shown because the authenticity of the received data could not be verified. What can you do about it? The issue is most likely with the website, and there is nothing you can do to resolve it. You can notify the website’s administrator about the problem.