On surface level both may sound and seem like the same thing but actually they are very different from each other. These are the ways they are different from each other-
Grad is meant to increase your knowledge about something you have already studied and have a degree whereas college studies are more generic and basic level that give you beginners knowledge about the discipline chosen.
The application process for grad schools is more intricate. The SOP is generally about how the degree will help you in terms of your career whereas for college undergraduate courses SOP is less academic and career-focused.
In grad school you have to be independent and no personal attention or spoon feeding will be given to you whereas in college professors will be concerned about you.
Studies in grad schools are tough as compared to colleges. Grad schools don't limit themselves to books.
