https://docs.safe.com/fme/html/FME_Server_Documentation/AdminGuide/Silent-Install-Windows.htm should help you on your way.

Thanks for your reply, I have checked above document but regarding load balancer and installing database on separate machine that part how to implement, I am not clear.

You'll have to configure the load balancer separately, if its an AWS load balance you'll more than likely be able to do this programmatically using the api.

Re the database, you'll have to script the following documentation:

https://docs.safe.com/fme/html/FME_Server_Documentation/AdminGuide/Provide_Database_Server-2-Tier.htm

Here is an example of a script i've used previously. Note, only use at as a guide, this is more a framework than anything else

https://github.com/thewabbit/fmeserverinstall

Thanks for your reply, I will check above links.

This is great Hamish, thanks a tonne for sharing this - excellent starting point