My phone has been acting up since the update
@AppleSupport ever since I updated, My iPhone7 won’t let me screenshot, I can’t turn off my phone or restart unless I reset it, & I can’t can close my lock screen. Can someone tell me what I can do?
You have more than one thing going on. Why can't you turn off your phone? What happens when you try? The next step in user troubleshooting would be a restore to backup. Connect the device to the computer and iTunes and restore to backup. If the problems continue, then restore the device to factory, and set it up as new, not using your backup.
FYI, you are not addressing Apple Support here, this is a user to user support forum, and Apple does not participate here. If you wish to contact @AppleSupport, that is a Twitter address, and you would need to use the Twitter app, or go to www.twitter.com.