What is unimpressive about your GPA - or your ECs - fencing, part time job, co-founded a club.
I think you’re just a wee bit hard on yourself.
You go to a private high school - so you should take advantage of the counseling opportunities afforded.
I can’t evaluate your UCs - but Brown, while unlikely, is not impossible. Same with UIUC - but I assume you re thinking CS which would be hard whereas Bio would be a match or even likely.
Purdue is very likely for bio and possible for CS. Pre-med is not a major btw - you can major in anything - yes, even History or Business, etc. and still be pre-med.
The schools you mentioned at the end would all be reaches - but that’s ok.
So here’s the thing - you don’t need safeties, likelies, matches, and reaches.
In fact, you only need safeties - maybe two - these are schools you can 100% get into, you can 100% afford, and you’d 100% be happy to be there.
So let’s say Merced and Riverside are safe and you are happy to attend - then you could be done. Or you could apply to only high reaches and it’s ok - because even if you got shot down everywhere, you have those two safeties to fall back on.
So your parents are willing to pay - so you’d have low cost opportunities in state and out of state if you wanted them - but you’d also have high cost opportunities.
Since, at the end, you mentioned some LACs and smaller schools, is this a preference? If so, you can look at any from - Occidental to Kalamazoo to Wooster on the LAC side and many more that will come with merit aid - to a Rochester, Miami (Florida), U Denver, William & Mary, or RPI type school, or it’s a bit more focused (no pure bio) but a Colorado School of Mines type in addition to the schools listed.
Good luck