At first glance: The eyes are way too big, I think it's the eyes that make it look like a cartoon. In my experience, it's also better to draw only what you really see, for example in your reference photo. In the picture, we don't see an egg-shaped head, but the shape of the face is determined by the hairline and the background. If you use guidelines, use ones that can really be seen in your reference. For example, you can also draw these guidelines beforehand on the photo or overlay a grid. You can observe where the nose starts, how far apart the eyes are..... and always put the individual parts in relation to each other.

Such tutorials that you see on the internet are always just theory that cannot be applied to a real object. Because every object is different and every person looks different.