Hi Kaliland1,
Thanks for reaching out to us, you seem to have a number of things happening at the same time with your iPhone. We'll do our best to help and see if we can get them resolved. As for the question on how to uninstall the update, Apple doesn't support going backwards with iOS versions, so we need to fix the version you have.
If the camera or flash on your iPhone, iPad, or iPod touch isn't working is the article you will want to follow for your camera.
If "Hey Siri" isn't working on your iPhone or iPad is a good resource when Siri isn't responding. It may also help with the dictation as well.
If you can't make or receive calls on your iPhone will help you with the phone calls.
These articles should help you with the issues you are facing. But should you still need help we recommend reach out to Apple Support by going to Get Support.
Take care!