Our galaxy is called the Milky Way. It is estimated that there are about one billion stars in the Milky Way. There are eight planets in our solar system. Their names are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The four inner planets (Mercury, Venus, Earth, and Mars) are terrestrial planets. (https://en.wikipedia.org/wiki/Milky_Way)
Terrestrial planet means it is mostly made of rocks or metals. Jupiter and Saturn are gas giants. This means they are giant planets made of mostly hydrogen and helium. Uranus and Neptune are ice giants. This means they are mostly made of elements heavier than hydrogen and helium.
Pluto is a dwarf planet that used to be considered a planet. It is one of the largest memebers of the Kuipter belt. The Kuipter belt is a collection of icy bodies located on the edge of solar system. Pluto was demoted to a dwarf planet in 2006. According to scientists the definition of a planet is a celestial body that is in orbit around the Sun, has sufficient mass for its self-gravity to overcome rigid body forces, so that it assumes a hydro static equilibrium (nearly round) shape, and has cleared the neighborhood around its orbit.
There are 5 officially recognized dwarf planets in our solar system. They are Ceres, Pluto, Haumea, Makemake, and Eris. With the exception of Ceres, which is located in the asteroid belt, the other dwarf planets are in the outer solar system. It is suspected anther 100 or so known objects in the solar system are dwarf planets. (http://space-facts.com/dwarf-planets/)
Astronomers have figured out that there are at least 146 moons in our solar system. There are another 27 moons awaiting official confirmation of their discovery. This number does not include the six moons of the dwarf planets. This does not include satellites that orbit asteroids either. Jupiter has a total of 23 confirmed moons. That is the most out of the 8. planets.https://en.wikipedia.org/wiki/Milky_Way