Please answer this.
Currently I only downloaded two games, Growtopia and Geometry Dash.
But when I browse with safari it just gets hot suddenly.
Which part is the hottest? Could be the processor doing something. I recall having my camera bug out with a tweak on my 5s which made it run constantly even when the screen was off and it got heated up like hell
It just gets hot near the top half, or where the camera is.
If it's especially hot, as in uncomfortable or even painful to touch, then you should take it back to wherever you purchased it from, or your local Apple Shop or w/e.
Show them how hot it gets and ask them what they can do about it. Whether it's a repair or replacement.
I know they can get very hot, and my old iPod Touch used to get really hot too when it was doing too much.
One thing you can do to mitigate the awkwardness of using it, would be to get yourself a nice case for it, but not one of those skin-tight ones. They can give you somewhere that's cool enough to hold it.
I researched a bit about if it is normal to be hot, but some others have complaints on Apple Support about iPhone 6 Plus getting hot while using it for a while.