In Galar, Moltres changed type from Dark/Flying to Fire/Flying. While the color from yellow and orange turns red and black like a smoldering fire in magenta.
Some other Pokemon will find it difficult to get close to this legendary bird, because from its body it can emit energy in the form of fire. Its wings are used to attack and expend these energies.
If you are still a beginner, maybe you will encounter a little obstacle to work on this Galarian Moltres coloring page. Especially on parts of the body that are like emitting fire. But by practicing and experimenting, you will become more proficient!