A Birth Chart or a Natal Chart, is a picture in time.
If you look at your chart you will see representations of what the sky looked like when you were born.
It takes into account the country and city you were born in, the position around the Ecliptic for each one of the Planets and the Zodiac signs above or beneath the celestial horizon of each of the Planets, and the time all of this took place.
It can be a very complex thing to do.
In your chart the astrology signs are formatted to look the way they did when you were born.
This is the base of your chart.
A chart has numerous components.
First, the divided circle, looking like a pie chart, will show the Zodiac signs and the Houses.
The Houses are in an independent, concentric (adjective: Having a common center) ring, it is like a circle within a circle.
The Houses provide a home for the Zodiac however, the Houses remain autonomous.
Think of the houses as a second background.
One by one, each of the Planets, the Sun, and the Moon, etc are all noted and their placements labeled.
The 1st "Planet" marked on your chart is not a Planet in the least, it is the Sun.
The sun comes first since the position of the Sun decides what Zodiac sign you are overall.
Each Planet (and that includes the Sun and Moon) will settle in a House.
That planet is then stated to govern that house.
Each of the 12 Houses commands a different facet of life.
When a Planet falls inside a House, it is certain that Planet is going to have a big influence over that facet of your life beyond whatever zodiac tendencies you have.
So now you know how a natal chart is made and what it contains.