Vitamin C serum for hyperpigmentation.

I'm a PharmD graduate and have done research on dealing with my hyperpigmentation. I have stubborn Whiteheads on my nose and normal to combination skin, my T zone gets oily after removing blackheads with a blackhead removing tool (earlier I used my nails to get rid of the gunk which lead to pigmentation) I also have hyperpigmentation around my mouth. After all the articles I have read I came to a conclusion that Vitamin C helps in reducing pigmentation and improving the texture of the skin when applied along with hyaluronic acid serum. Is VC15 vitamin C serum good for someone who is starting out with Vitamin C? And can a toner with 5% glycolic acid toner help in resolving blackhead issue by removing excess oil and minimizing pores? Kindly please reply to this as I'm eagerly waiting to incorporate both of them in my skincare routine. Thank you.