Action base on switch trigger-status

Hi,
How Can I create an automation base on a switch statut ?
something like :
If switch is ON then Action (start Script/automation)
If switch is Off then action

It this possible to do in ONE automation and not 2

Seem to be a basic case, but I can’t find the right keyword search

https://community.home-assistant.io/search?q=combining%20automations