my phone won't turn off or let me go into any apps, how do I fix that?

Try and Force Restart your iPhone exactly as shown below and see whether that resolves the issue:

• Press and quickly release Volume UP button
• Press and quickly release Volume DOWN button
• Press and Hold the SIDE button until an Apple logo appears then release the Side button (Can take up to 20 seconds. DO NOT release Side Button when invited to Slide Power OFF). 

Axel F.

I have the same problem and I went to Geek squad at bestbuy and they fixed for my.