I have to learn Russian.
I have to bring textbooks.
I have to answer teacher's questions in lessons.
I don't have to take exams every year.
I have to do homework.
I don't have to read newspapers and magazines.
I don't have to take photos.
I have to wear a school uniform.
I don't have to join school clubs.
"Have to" обозначает "обязан", например, I have to do my homework.- Я обязан делать домашнее задание.
"Don't have"означает не обязан, но не ставит категоричное "нет"- можешь делать, если хочешь. Например: "I don't have to take exams every year"-Я не обязан сдавать экзамены каждый год.