About the detail step how to add devices in icinga1

Hello Team,
I have setup with new ICINGA1 for monitoring purpose. Can someone please help me to know how to add network devices on the webbrowser for monitoring device.

Please NOTE: We have nagios now as active monitoring tool which is going to be migrated to icinga1.So is it possible to take backup of it all at once?
If yes,please help me with the process.?It will be really helpful

Icinga1 is EOL and if you are moving Nagios to it, it’s a bad idea (consider Icinga2 instead).

With that said, we currently use NagiosQL for configuration management of our only remaining Icinga1x instance. It’s not perfect, I don’t know how to set it up, but it does work for creating hosts/services and other objects within a web browser.

If you use Icinga2, you can use the Icinga Director module. It is much cleaner and more powerful to use.