The most common action of an Infinite Content is showing an iframe window. It is a very versatile window that can be located on any area of the player and occupy all the space it may require. To set the area the window will occupy, you will have to modify the size and position parameters you will find on the General submenu of the Properties panel of Infinite Content.
The Width and Height parameters allow you to define the size of the window, like the Origin, Top, Left, Bottom and Right parameters will allow you to define the relative position within the canvas. If you need to, you can consult the articles Adjusting the position of an element and Resizing an element to know further details about such parameters.