If you see Nginx SSL Error 0200100D like below, it means that Nginx is not allowed to access the SSL certificate file. This is usually a SELinux issue. You can fix it by using restorecon command to restore the SELinux context of the certificate file.
nginx: [emerg] cannot load certificate "/etc/nginx/ssl/cert.pem": BIO_new_file() failed (SSL: error:0200100D:system library:fopen:Permission denied:fopen('/etc/nginx/ssl/cert.pem',...ew_file:system lib)
Check If SELinux Is Enabled
sestatus
# output
SELinux status: enabled
Restore SELinux Security Contexts to Fix Permission
restorecon /etc/nginx/ssl/*
