The steps are:
1. Go to openlitespeed admin page (:7080), go to Virtual Hosts and add a new vhost.
2. Fill in these details:
Virtual Host Name: *
Virtual Host Root: /home/default (or any folder you want)
Config File: $SERVER_ROOT/conf/vhosts/defaultvh/vhconf.conf
Folow Symbolik Link, Enable Scripts, Restrained - all set to yes.
3. Add the vhost, then click the view button and go to General tab.
4. Click on the pencil icon to edit the first group, and set the following:
Document Root: /home/default (or the folder you defined on the previous step)
Domain Name: *
5. Click on save and then do a graceful restart using the icon on the top.
6. Go to Listeners, click on the view icon from the Default, port 80 line.
7. On Virtual Host Mappings, add a new one, choosing * as virtual host type * on Domains.
8. Do a graceful restart of LSWS.
9. Place the files (html, images, etc.) in the Document Root defined earlier.
10. Enjoy!

ps: if you still get a 404 error page, run this command:
chown -R nobody:nobody /home/default

Have a nice day everyone!

source: https://forums.cyberpanel.net/discussion/925/default-server-webpage-points-to-404-page