No planet! However, Venus has no moons and is not much smaller than Earth.
Mercury is the planet that is one quarter the size of Earth and has no moons. It is the smallest planet in our solar system and is the closest planet to the Sun.
The planet you are describing matches the characteristics of Venus. Venus is nearly the same size as Earth, has no moons, and its atmosphere is mostly composed of carbon dioxide, with thick clouds of sulfuric acid.
No planet is exactly the size of Earth. Venus is close to Earth's size but slightly smaller.
In terms of radius, Mars is about half the size of the Earth. It also has two moons called Phobos and Deimos
Moons of planets are typically called natural satellites because they orbit a planet just like how the moon orbits Earth. These moons vary in size and composition depending on the planet they orbit.
The planet that is half the size of the earth, has 2 moons, and has an atmosphere of mostly carbon dioxide is Mars. The average length of a day on Mars is 37 minutes longer than that of the Earth.
Venus
Venus Its sister planet
the planet venus.... size is about the same
they both have craters
Earth.
Ganymede, one of Jupiter's moons, is the largest moon in the solar system and is even larger than the planet Mercury. It has a diameter that is about 0.41 times that of Earth's moon.