I'm a special education teacher. I felt a calling to work with children with autism and followed my passion.
teacher (also called a school teacher or, in some contexts, an educator) is a person who helps others to acquire knowledge, competences 
Yes, I work with students who have difficulties in adjusting to their world. It is very rewarding.
the role of teacher may be taken on by anyone
Do you have any teachers in your family?
most countries, "formal" teaching of students is usually carried out by paid professional teachers.
Yes, that is true. I've even taught overseas before. I taught for two years in Qatar.
teacher's role may vary among cultures