Be careful with zip. You need to make sure symlinks are preserved (--symlinks in Info-ZIP). The default behavior of tar is what you need, might be better:
tar cf letsencrypt.tar /etc/letsencrypt
You'll need to be more specific as to where you run into trouble. Does your Apache config on the new server work OK?
Now when I try to open my wordpress site I receive this message.
Safari can’t open the page “https://www.lojadasroupinhas.com.br” because Safari can’t establish a secure connection to the server “www.lojadasroupinhas.com.br”.