None of my apps are working

Force restart your iPhone:

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky. If done correctly this will always work unless the phone has a hardware problem. 

But why can’t you do a backup?

Hello~ What happens when you try to use them? Message? Try clicking on below…

Force restart iPhone - Apple Support

~Katana-San~

Benji1820 wrote:

I need help with my phone

You will have to explain what kind of help you need. This link can help you focus your thoughts→How to write an effective Apple Support Communities post