Our solar system is a small group of objects orbiting our star the sun. It is locared in the galaxy called the milky way. Earth is unique in the way that it is the only planet known to harbour life. This life is possible because of the abundance of liquid water. Scientists believe that the key for life is liquid water, and there is only a very small distance from stars where this is the case, it is called the goldilocks zone and Earth lies in the middle of it, making it the perfect home in an otherwise inhospitable universe.
Other planets in the solar system are different from Earth, for example they are made up of different things (metals, gases, etc) and have different atmospheric compositions. On Earth the atmosphere is mainly nitrogen then oxygen some argon and traces of other gases like carbon dioxide. However, the atmospheric composition on other planets can be toxic for example Venus’s atmosphere is 96% carbon dioxide.
There are other things in the solar system like moons, these are similar to planets but do not orbit the sun, they orbit a planet. For example, Europa is a moon because it orbits Jupiter.
Our solar system is made up of four terrestrial planets: Mercury, Venus, Earth, Mars and two gas giants: Jupiter, Saturn and two ice giants: Uranus, Neptune. It also includes many asteroids and dwarf planets. There is a large asteroid belt in-between Mars and Jupiter and after Neptune there is the Kuiper Belt a massive astroid belt containing many dwarf planets. Gas giants tend to be larger than terrestrial planets and, in this case, they are and are the 5th and 6th furthest planets from the sun. The two ice giants are the 2 furthest planets from the sun.