How to use Reverse Proxy in OpenLiteSpeed?

Question

I want to deploy my nodejs application that contains backend and frontend for my application in openlitespeed.

I run both of them using pm2 autorunner and get the port that i setup earlier (For example i using port 8080). How can i use reverse proxy like nginx in openlitespeed? is there are step by step to do that?

i expect it to run in url like this localhost/downtime-app without using port

Actually i already set my index.html of my frontend to configured like php but when i refresh the page it will return page error 503, and i already add .htaccess in directory of my builded nodejs fe but it not working, so i want to use reverse proxy if it possible.

information : i use .htaccess like this

<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteBase /
  RewriteRule ^index\.html$ - [L]
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule . /index.html [L]
</IfModule>```