Whenever you decide to sell or give your device away, it is real important for you to Sign out of your iCloud (Apple ID) otherwise the next person would not be able to use the device & would be stuck on the image you see here.
So Before you buy an iPhone, iPad, iPod touch, or Apple Watch from someone, make sure that the device is erased and no longer linked to the previous owner’s account. Ask the seller whether or not they've turned off Activation Lock, then follow these steps:
Turn on the device on & go to the settings, If you see an email account on the very top, the device hasn't been erased & still has the iCloud Account
At this point, you can ask the seller to completely erase the device by going to Settings > General > Reset > Erase All Content and Settings. Don't take ownership of any used iPhone, iPad, or iPod touch until it's been erased.
Once the reset is finished, begin the device setup process by connecting to Wi-Fi anywhere. If you're asked for the previous owner’s Apple ID and password after connecting to Wi-Fi, the device is still linked to their account. Hand the device back to the seller and ask them to enter their iCloud information. Once you bypass the whole setup you will see the the image below, & after that, if you reach the icon screen, the device is fully unlinked from the previous owner's iCloud account.
Don't take ownership of any used iPhone, iPad, or iPod touch until it has been removed from the previous owner’s account.
If you buy a device that's still linked to a previous owner's account, contact them as soon as possible and ask them to erase the device and remove it from their account.