"I have to write many notes."

Translation: Tôi phải viết nhiều ghi chú.

[bui_khong_minh]

I would rather say "ghi bài" at school

[davidd1235]

Tôi cần viết nhiều ghi chú
Wasn't accepted... Is cần that much different than phải in this context?

[Naccio42]

The difference between "phải" and "cần" is pretty much the same as the one between "have to" and "need to": the former conveys obligation and the latter necessity. Even if in colloquial English they are often used interchangeably, I think that while learning a new language it's good for this distinction to be enforced.