I'm not hungry in the mornings. Is that normal?

Yes. Lots of people who find it hard to gain weight aren’t hungry in the morning. Morning appetite is mostly habit: eating your first meal even when you don’t feel like it will make you hungrier in the mornings.

If a full breakfast feels like too much, start small, like a smoothie, a milky coffee, yoghurt with granola, or toast with nut butter, and build up.