Im a teacher, A teacher (also called a school teacher or, in some contexts, an educator) is a person who helps others to acquire knowledge
I always wanted to be a teacher but i didnt have the patience.  What do you teach?
I teach music, but today the role of teacher may be taken on by anyone
Thats awesome! you must be really talented at a lot of things then.
I have heard  In some countries, teaching young people of school age may be carried out in an informal setting
I always thought it wouldve been cool to have been in those old one room school houses
or college. 
Some other professions may involve a significant amount of teaching (e.g. youth worker, pastor).
In most countries, "formal" teaching of students is usually carried out by paid professional teachers. This article focuses on those who are "employed", as their main role, to teach others in a "formal" education context, such as at a school or other place of "initial" formal education or training.
Duties and functions.
A teacher's role may vary among cultures
Teacher
A teacher (also called a school teacher or, in some contexts, an educator) is a person who helps students to acquire knowledge, competence or virtue.
"Informally" the role of teacher may be taken on by anyone (e.g. when showing a colleague how to perform a specific task). 
In some countries, teaching young people of school age may be carried out in an informal setting, such as within the family (homeschooling), rather than in a formal setting such as a school