Control Center is great because it allows you to quickly do all kinds of useful things like turn WiFi, Airplane Mode, and Do Not Disturb on or off, lock your screen orientation, adjust volume levels, open your phone's calculator, and use your iPhone as a flashlight, among other things.
What's not so great is swiping up from the bottom of the screen while using an app (especially when that app is a game) and accidentally bringing up Control Center.
To prevent Control Center from opening while you are using apps go to Settings>Control Center and toggle Access Within Apps off.
You can also choose whether or not to allow access to Control Center from your lock screen. It just depends what is more important to you, limiting access to your iPhone, or being able to quickly access Control Center's features without having to unlock your iPhone.