This inforgraphic, "From Classlink to "turn in", 10 steps to turning in an assignment in Google Classroom", is just one way to complete and turn in an assignment in Google Classroom. How many way's can you find to turn in an assignment in GC?
Open Classlink
Watch this gif to see where to click to always find a link to open Classlink. (HINT: Classlink is set as your home page)
Open Google Classroom
In this gif you will see how to open google classroom by clicking on the icon in classlink.