Ex plorer: a Viewfinder is, more or less, the part that differentiates the cheap from the very expensive.
The really expensive Cameras have a viewfinder that looks through the lens. Allowing you to, exactly, frame the photo you're about to take. It's an intricate process and adds zillions to the cost of the camera.
Make do with just a rear screen and he'll get a cracker for his £300.00.
There are a few cameras that have a wee hole, top left, that you can put your eye to and see roughly where the camera is pointing. While this is OK for "snaps", it is nigh on impossible to accurately gauge where the camera is pointing so every shot is very much a hit or miss affair, or more likely you'll cut off the top of someone's head!