If

To add a trigger condition, click in the area “IF” on the button “add” and a window will open where you can add a trigger condition.
For example, if you add a button then you have three options:

Pressed
More press
Double press

If you want to invoke a scene only via the app, you do not need a trigger condition.

If you wish to add several “IFs”, the scene can be invoked by each individual trigger condition, independently of each other.