I wanted to know the exact command from linux cli to check if the applicaiton hosted on the server

Many ways to find, if application is hosted on servers. Google is best source to find command. Updating clue.

1. Validate LAMP setting
2. Check how many service are enable to server.
3. Try to open app one by one http on browser(it's time consuming).
4. etc

for curl to give the HTTP response code:

curl -s -o /dev/null -I -w "%{http_code}" http://www.example.org/