If your iphone or ipad for that matter does not turn on anymore no matter how many times you press the power button or even if you connect the usb charging cable there is a good chance it is not broken you don’t have to rush to the repair shop or replace your phone and you can easily fix it yourself.
The first thing to do is to thoroughly charge the phone leave it connected to the charger for at least an hour and wait if it springs back to life if that doesn’t happen you will have to perform a soft reset which should not delete anything from your iphone or ipad so all the apps music files and photos should be left intact to do that on iphone 6 and earlier models you have to press and hold power button and home button of course that means you need to have a working and functional home button which may be a challenge on iphone 6 which is notorious for having a broken home button most of its lifespan on iphone 7 and newer you have to hold the power and volume down button together press and hold them both for at least 10 seconds and wait for the apple logo to appear