How is the same side of the moon always facing the Earth?

The Moon's rotation is tidally locked with the Earth.

The Earth's gravity caused a "tide" on the Moon just as the Moon causes tides on Earth. The Moon's material didn't "flow" like water but the Moon changed shape a tiny bit. This caused the Moon's rotation to slow (just as it causes the Earth's rotation to slow). After the Moon's rotation rate reached the same as its orbit (one turn for each orbit), the tidal effect no longer slowed the rotation.

As the Moon goes around the Earth the Moon turns at just the correct speed to keep one side always facing the Earth. The tidal effect will keep it that way.

Another consequence of tidal forces is that the Moon moves away from the Earth and it takes longer to orbit the Earth; the lunar month becomes longer. In the future, the maximum length of the day will be reached when the Earth rotates at the same speed that the Moon orbits. In other words, the day and the month will have the exact same length, somewhere near 47 of our present 24-hour days. At this point the Earth's oceans will have no tidal changes and the Moon will no longer be moving away. That is the theory but the Sun will burn out before that happens.

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This is because the moon is "tidally locked" to the Earth.

This mean that the moon makes 1 revolution around the earth and at the same time rotates once.

so it has a 1:1 orbital resonance.

We always see the same side of the moon because its going around the earth, but spinning in sync to the revolution. i.e the moon rotates once every revolution around the earth, so the same side always faces us.

did I explain it clearly enough?

The moon rotates in the same amount of time it takes to orbit the Earth, so it "keeps up" with itself.

Try this:

Find a tree and face it. Now walk around the tree at the same time rotating at the same rate so that you turn around one full turn in the same time it takes to go around the tree once. If you are rotating in the same direction as you are walking, you will always see the tree, but the background will change (that proves rotation, when the background changes).

The Moon rotates in the same time that it orbits Earth.

The moon does rotate. At its equator it rotates at 10.3 mph. At the same time, though, it's moving around Earth at 2,286 mph. These two speeds causes only one side of the moon to face us.

It does rotates, but its rotation period, its day, exactly match its rotation period around the Earth, so we only one side of it.

the moon is a world without air. its gravity is too weak to hold an atomosphere around it , if you stood on the moon , the sky would be pitch black,even in daytime there is no air to scatter the sunlight and make the sky blue