Hi there, I can see you’re a new poster. Please don’t take this the wrong way, but you’ll find that lots of users on this forum are extremely elitist and might look down on you for being at a ‘low level’ in maths. Ignore them. Just wanted to give you the heads up.
I would say that sounds like a later topic from Algebra 1. Polynomial division might not be hit on until early Algebra 2, so that’s where I would put you.
It’s a site run by the city of Oswego, NY (home of the SUNY university, but this one is about high school.) It’s intended to help kids prepare for the Regents Exam, but it’s a great resource for anyone taking those courses.
For the most part that is Algebra 1 ( FOIL method, adding & subtracting polynomials and binomials), with a little Algebra 2 ( multiplying & diving polynomials and binomials).