learn later on

My son just come home from school after three hours of class. He shows me his lesson. He is getting better at coloring the drawings, he is coloring inside the lines now. But he still can not spell his name right. I asked him if he wanted me to teach him how to write he said he knew already and perhaps his teacher is going to teach him. He is always like that every time I asked him to write, he doesn’t want me to teach him because I am not his teacher. I told him that I need to teach him so that he can write his name. Sometimes he will let me and sometimes not. I don’t want to force him, he is only four years old, when I started writing my name I think I was six years old so, I think he will learn later on.