At a glance, IT (information technology) careers are more about installing, maintaining, and improving computer systems, operating networks, and databases. Meanwhile, computer science is about using mathematics to program systems to run more efficiently, including in design and development.
While computer science education isn’t necessary for an IT career, some IT education is fundamental for a computer science degree that later leads to job opportunities. IT can be specialized in many different ways, but CS graduates have opportunities immediately available to them that IT qualified workers don’t. For more details: IT vs computer science