Windows 7 is End of Life. Some of the certificates that validate websites haven't been updated since February 2020. If there is invalid certificates then windows will display that message across any browser that uses windows certificates. It will be a better situation for you to upgrade to Windows 10 or buy a reasonably priced good performing Windows 10 computer that is designed for Windows 10.
As time progresses more and more certificates will expire and you will see more errors. There is a workaround but it's time consuming and irritating processes. I won't help with that. It won't last long anyway.