Parents teach their children the most important and necessary things; they are the best teachers.

From the birth to death, a person goes through different phases of life and faces many people as his/her teachers. His/her life begins with the first teachers, who are parents and continues with teachers at school, gym, college or university. All of these teachers are good and necessary and can play important roles in navigating and shaping someone's life. However, the first teachers, who are parents, are the best teachers.

Parents teach their children the basic but necessary things. When a small child starts growing, his first teachers, his parents, help him how to walk. Later, they teach him how to talk, eat food, wear clothes properly, and communicate with the others politely. All these things taught by parent in early stage of life demonstrate who you are. They define you in the society. These rudimentary but paramount things are necessary to be taught to the children before they want to enter a kindergarten or school where they will face their forthcoming teachers.

The intimacy which exists between the children and the parents can solve many problems the children encounter. In early stage of life, a person lacks experience. Hence, he may face many problems. Furthermore, many children don't feel good to share their problems with their contemporaries, friends or their teachers at school or college, but they have their parents to refer to. They can share their problems with their parents without any hesitation and premonition. In response, parents never forego anything they can do or they can tell their children to put an end to their problems.

In life, we can have many teachers and we might learn many good and effectual things from them but parents, the first teachers in every body's life, are the best teachers. They teach their children the most important and necessary things. Moreover, the intimacy which exists between parents and children doesn't exists between anyone else and the children.

good
instead of saying , who are parents,.. just say ,parents, or whose parents... make it a little different and beautiful.
all things are taught. ( passive)
don not use you in your essay. one, people, children, individual, ... are better.

You need to improve the presentation of this sentence. There's lots of redundancy I find there :( This is what I suggest;
Everybody finds many teachers in different phases in life.
When a small child starts growing, his first teachers, his parents, help him learn how to walk.
They define your character in the society.
Focus more on the main idea and try to avoid repetition of ideas.