add module problem

I’m new to drupal. When I right click, copy link, and paste a new module link, I always get the message,
“Failed to fetch file due to error “cURL error 77: SSL: can’t load CA certificate file /Applications/DevDesktop/common/cert/cacert.pem (see”
Unable to retrieve Drupal project from”
or whatever the module is i want. How do I get my modules?

Drupal version: