Apps are gone from home screen & all pages?

I picked up my iPad (iOS 11) turned it on and for no reason at all, every single app is gone from the home screen and all the other screen. The background turned brown and the only thing visible on the screen is the tool/app bar along the bottom of the screen. I did search for some of the missing apps, and they are still downloaded. I also looked in setting—restrictions to make sure nothing was disabled. How do I get all my apps back on all pages?

PS my 4 yr old son was using FaceTime on my iPad yesterday.