Guest toilet so that a lot of light comes in.
If you want light in the room, then make the windows wide with the same area instead of tall. With a higher positioned window, you might even be able to skip the frosted film and have even more light in the room, because the film also absorbs quite a bit.
Children’s room - the windows face the garage/carport. Therefore, they are just windows and not floor-to-ceiling.
Normally, one says the window size should be at least 1/8 of the room size. In your children’s room, it is less, and the listed measurement is also the rough construction dimension. The window frame will reduce the glass area considerably. The drawn-in wardrobe also extends slightly into the window.
knee wall is 1.50m
Then, in my opinion, the elevations are only a very rough guideline.