What is an IFrame?
Interacting with Elements within IFrame
By default, when the test starts, we will be in the main body of the page and we need to explicitly switch to an Iframe to interact with the elements inside that Iframe.
The only thing you need to take care is that if you get a "No Element found" error in a step or if the element is not clicked as expected, most probably there's an IFrame within which the element is located.
You would just need to check if there's an IFrame and if yes, switch to it. You can use the Switch NLP for that.
And to check if the corresponding element is within an IFrame, the easiest method would be to right click the element and see if there's an item called 'Reload Frame' or 'View Frame Source'.