All three have excellent nursing programs
. BCIT looks for a minimum of 60 postsecondary credits (due to high number of applications creating competition). I think Langara and Kwantlen accept students directly from high school? But it is best to confirm that. Again, due to competition, that doesn't necessarily mean you will get accepted straight from high school.
It is never a waste to apply, but have a back-up plan. Take first year university courses that will help you, and might lighten your load later. English, Biology, Psychology, etc. Volunteer some more. Basically, keep beefing up your application as you wait - you will get accepted eventually!
Your last paragraph was a bit concerning to me. Most university programs these days are competitive, and the application process is not necessarily simple - so not applying to nursing for that reason is a bit strange. If you aren't certain nursing is the career for you, I would encourage you to do some research on the realities of nursing, and do some volunteer work, including shadow shifts, so you can see if nursing is right for you.