I am planning to buy the Canon EOS 2000D camera. I know it has a built in flash but I don't know where it is (I also looked in the specifications/other sites)? Is it a pop-up flash in the top and middle of the camera?
You can check this photo to see where is the flash. The simplest way to use/open it is to press the button below the flash (marked with flash sign).
Also you can check on page 198 of the camera manual how to enable/disable flash.