The Solar System
Our solar system has the Sun (a star), 8 planets, dwarf planets (Pluto, Ceres), moons, asteroids, comets, and dust. The inner rocky planets: Mercury, Venus, Earth, Mars. The outer gas giants: Jupiter, Saturn, Uranus, Neptune.
A planet must: (1) orbit the Sun, (2) have enough gravity to be spherical, (3) have cleared its orbital neighborhood. Pluto fails #3 — it's a dwarf planet.
Seasons and Moon Phases
Seasons are caused by Earth's 23.5° axial tilt — NOT distance from the Sun. When your hemisphere tilts toward the Sun, you get more direct sunlight and summer.
Moon phases are caused by our changing viewing angle of the sunlit half of the Moon as it orbits Earth. New Moon → Crescent → Quarter → Gibbous → Full Moon (and back).