Green Screen in PhotoShop

I'm a teacher, and we are trying to create a movable button booth.  I will take the photo of the kid in front of a green screen with a camera tethered to my MacBook Pro, and then I will need to print the photo on a photobooth printer.  (We have been using an I-Pad with the simple DoInk app and using Google Photos to transfer but it relies on the Internet connection, and we've had problems).

Since I won't always have WIFI at these events, I need a stand-alone setup.  So I'm wondering if I need to purchase a stand-alone version of PhotoShop (Now I have the CC version), and if so how much that is.  

Also, if anyone has any other suggestions about how I can create this setup in an easier way, please let me know.  Thank you!

Amanda Triplett

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