Xcode checkbox tick determines which page displays when you click next

I am pretty new to programming and Xcode so I am hoping someone can help.

I am writing an App using swift and I have a table array with checkboxes as per the attached image below. As you can see, the next button in the top right is disabled. What I want to happen is that when I click one of the checkboxes this next button becomes enabled, but this is not happening:

Screenshot table array

I have tried several things:

script attempts

(Please excuse the silly mistakes in the earlier ones with the missed bracket! Please also excuse the dreadful image, I am not allowed to attach more than 2 images) In any event, I think it is pretty clear that I don't really know what I am doing, please help.

The next step is that the page that displays when you click the next button will be determined by which of he checkboxes has been ticked. I don't even know where to begin with this, I have done some research on NSPredicate but I'm not sure if this is the answer, I cannot find instructions on how to do what I need, any help would be appreciated.

Thanks