Lighttpd

Hello! I am new to Linux and lighttpd. I have a domain, which is connected to CF. The subdomain is configured and redirects to the main site. How to make lighttpd recognize my subdomain and allow me to put my own content? The only thing I saw on the internet has this format and it isn't working (or at least not in /etc/lighttpd/lighttpd.conf). Any help would be appreciated:

$HTTP["host"] =~ "website" {
    server.document-root = "path" 
    accesslog.filename = "path" 
}