Yep, it should.
Probably best if you try it locally or on a staging server first, if you’re concerned.
For your *.example.com server, are you using a wildcard certificate? If so, you’ll need to configure Caddy to use a DNS provider module. See here:
Your config would probably look something like this:
example.com {
root /var/www/html
encode gzip
php_fastcgi unix//var/run/php/php7.2-fpm.sock
file_server
}
*.example.com {
tls {
dns <provider> <config>
}
root * /var/www/html/{labels.2}
encode gzip
php_fastcgi unix//var/run/php/php7.2-fpm.sock
file_server
handle_errors {
root * /var/www/html
rewrite * /{http.error.status_code}.html
file_server
}
}