Do you need a teaching degree to teach?

You can teach anybody anything you know. But to be a teacher in a school, most school systems will require a teaching certificate.

You do not need a teaching degree in order to teach in a school. You only need a teaching certification, which you can get without having any sort of degree in teaching.

Teaching in colleges and universities seldom require a teaching certificate, but they usually want a 'terminal degree' in the field that is being taught, such as a Medical Degree or a PhD or a Law Degree.