It was a valid piece of advice, which you did in fact ask for.
The brutal, honest truth is the entire school system is a scam. Yes, if you do in fact seek knowledge, College can benefit you. But College is not for everyone. Not these days. You know what you need to prepare for? Spending lots of money on classes and books. Spending LOTS of your free time writing papers, researching, and just dedicating your free time in general to school. If you're applying for a community college, chances are that you will get into whatever community college you apply for. But if you're aiming for anything other than a community college, then yes. Expect to apply to about a dozen colleges [or more], because you will get rejected by most of your choices, unless you were a wiz kid in High School [took a lot of Honor classes, did after school curriculum like sports, joined a bunch of clubs, got very good grades, etc.].
I think it's safe to assume that you're going to college to get a good paying job. Well, prepare for even more good news! These days, most "good" paying jobs require higher education than your basic AA degree, meaning you're going to need to spend at least 4 years working your ass off in school, just to go out and work your ass off in the real world. That's assuming you get hired, because the working world these days is very brutal. To work at McDonalds now, you need a high school diploma, just as a comparison.
Im not trying to discourage you from going to college. Because if you want to get a good job, you'll have no choice but to go to college [with few exceptions]. While there are JUST as many positives to college life as all the discouraging things I've mentioned, this is what to expect. Everyone has their own ways of preparing for things like tests, and if you haven't figured out how to properly study yet throughout High School then I suggest you start researching study techniques now. Because unlike High School, College is not going to hold your hand. You will be given an assignment, you will be given a due date, and you will be expected to be an adult and keep track of your own progress. There will be no reminders of when assignments are due [some professors might, but it's better not to expect them to]. Professors will not care if you are in class or not. Once you hand over your money to College, you're on your own.