my flashlight won't turn ON and my front camera is not working

Hi olaboi19!
Thanks for joining Apple Support Communities! It appears that the flashlight/back camera flash has stopped working on your iPhone 5s on iOS 9.3.5. This may be a hardware or software issue at this point so I'll be glad to help you figure out which it is.
1. How to back up your iPhone, iPad, and iPod touch -- Before beginning, please be sure to have a fresh backup to keep your personal information safe.
2. Use iTunes on your Mac or PC to restore your iPhone, iPad, or iPod to factory settings -- You'll need to use iTunes to completely erase your iPhone. Using the settings on the phone only removes your personal information.
The first time through, select "As a new iPhone" and skip logging into iTunes & App Store and iCloud. Once your phone is back to the home screen, see if your flashlight/back camera flash is working. If it isn't, Contact Apple Support . If it is, continue to the next step.
3. Restore your iPhone, iPad, or iPod touch from a backup -- This article will guide you through the steps of returning your personal information to your phone.

Cheers!