Question / Help preview stream not working

[HDRated]

Hi i just started getting into the stream biss and i was adding an over lay to my stream. the overlay was too big and i didnt know how to fix that so i did reasearch i think you have to do it by pressing preview stream. but it wont let me click it. it is kind of grayed out so it doesnt even give me the ability to click it. Any help?

 

[dodgepong]

Preview Stream just lets you see what the stream will look like before it goes live. If you're already streaming, you can see the preview window already.

To fit the overlay in your stream, select the image and press Ctrl+F.

 

[HDRated]

what do you mean press ctrl+f i play league of legends and the over lay doesnt fit my hub