Blue eyes! (from right is natural eye color) A Golden British cat can't have blue eyes, only when he is small, even then it's very hard to call his eyes blue.
Color Saturation. Here, the saturation is increased throughout the photo, but you can make the Christmas tree in the background remain unchanged.
In the same step (same picture), whitening the chin and neck hair. Here you can see that by increasing the saturation the white hair has become a bit golden, this is because the golden kitten's white hair is also a bit golden and by increasing the saturation the neck hair becomes golden, so you need to bleach the neck. In this picture you can see that the white hair from the bottom is still a little golden, I left this strip unbleached on purpose so you can see the difference.
If the photos are very beautiful, it means that a professional took the photo and probably post processing was applied to the picture, so ask for a video call in normal daylight. Ask to bring the kitten up to the window to appreciate his natural colors.
I'm not saying here that Photoshop removes all the spots that spoil the photo. Our cattery is not engaged in "painting" the pictures, so all pictures show the real colors and defects of the kitten.