what is the difference between introduction to computer science and introduction...

if you take intro to computer science, you have to take intro to computer science lab.

Any time there is a class with a name identical to another, except for being a lab, it is required to take both. One is class time where you are taught what to do, the other (the lab) is when you practice what you learned, under supervision, with special equipment (chemicals, or computer w/ software) that you wouldn't normally have at home.

The first one is most likely where one studies from the text book then lab is where you apply that knowledge with hands on learning. Meaning you work with the actual thing in lab to apply what the text and instructors have taught in the classroom.
Computers are not as complicated as some might think and the Internet puts the world right in front of you. Google search engine is a valuable tool to find info and resources. I use it daily to access info on car repair or "how to" sites. Being a guitar builder I can find materials and techniques from around the world which I could not find anywhere else.