Button only appear after user has visited tabs?

Hello all, and thanks in advance for your advice.

I'm working on a slide with 3 tabs and I'd like the learners to HAVE to visit each tab before they can navigate to the next slide.

That being said, I'm using an eLearning Brothers template slide with tabs and for the life of me, I can't figure out how to make the 'continue' button appear ONLY after they have visited each tab. Any tips or best practices are super-duper welcomed.