Use Apache to set a file server

<VirtualHost>
        ServerName file.yingshaoxo.xyz

        DocumentRoot "/var/www/html"
                                                           
        <Directory "/var/www">                                                                 
            Options Indexes FollowSymLinks MultiViews                                        
            AllowOverride None                                                               
            Order allow,deny                                                                 
            allow from all                                                                   
        </Directory>
</VirtualHost>

systemctl restart apache2

When you finished doing this, you could remove /var/www/html/index.html, then add some folder or file into /var/www/html/

In the end, you will find your file right in file.yingshaoxo.xyz