How do I get all my disappeared apps back?

How do i get all my apps back?

I was using Snapchat and it randomly glitched out of the app and when I opened my phone again most of my apps had disappeared including the App store, Snapchat, TikTok, Instagram, Send-it, Pinterest, Spotify and more. I have tried turning my phone off and on multiple times with no success and I have also tried resetting my home screen in settings but my apps are still missing. Can someone please help me fix this problem? And can someone tell me why this is happening?

[Re-Titled by Moderator]