What to choose, a set of panels in one scene or different scenes?

Question

Unity

Hello Khabrovtsy.
There is an application for mobile devices (android, ios), which has several screens and VR mode.
Now all the screens that guide the user to a choice are made in one scene. Just one element is hidden another is shown. VR mode is made on a separate stage, but now it's not about him.

selection screens

Now, in order for the button to return to the previous screen to work, you have to save the transition stack.
General data for the application is stored in a static class. Sometimes if the user switched to another application on the phone, and then returned after a while, my application crashes and closes. If I understand correctly, this is due to the reloading of the scene and the static class whose data is filled in in previous scenes.

Actually 2 questions.
- Would it be correct to arrange all the screens as separate scenes?
- How to properly store the general data of the application if the user's choice is made on other scenes?

Thank you in advance.