"Safari can't open the page" unless you reload 1-3 times and sometime not even then

Almost every link I click sends me to a page saying Safari can't open the page because "Safari can't establish a secure connection to the server." Amazon. Walmart. My bank sites. Reference sites. You name it. Refreshing usually helps, but now it's sometimes requiring more than one refresh.And, it's getting worse. Today I had to switch to Chrome to pay a bill. Safari refused to load it, despite multiple refreshes. These sites work fine in Chrome, but I truly prefer Safari. I know next to nothing about computers. Also, they work fine on my phone and other devices using the same wireless network. The problem doesn't go away if I try to browse to the same sites in Private Mode.

I'm running OSCatalina10.15.3 and Safari 13.0.5.

Any easy fixes out there?