Yes, absolutely. That’s one of the things Caddy excels at.
You didn’t fill out the template, so I’m unsure how to help you. How are you running Caddy? What’s in your logs? Are you sure your other server is running and can be reached from Caddy?
Those error logs don’t make sense with the Caddyfile you posted above. Please post your full, unredacted Caddyfile and logs.
Also, please put ``` on lines before and after any config/logs/code you post here, it will preserve the whitespace and make it easier to read. It’s not necessary to put it in pastebin.
Your logs show that you’re trying to get a wildcard cert for *.opybox.com but your config doesn’t have that… that is why we are confused. We require full, undredacted config and logs so we can help troubleshoot problems.
To get wildcard certificates, you need to enable the DNS challenge. That requires building Caddy with one of the DNS plugins to add support for that: Automatic HTTPS — Caddy Documentation