What are effective methods for removing freckles and blemishes?

I'm worried because I've been getting a lot of melasma and blemishes lately. I'm even more concerned now that the season for more outdoor activities is back. I know the best approach would be to be careful to prevent them from forming in the first place, but... what treatments are effective for removing melasma and blemishes that have already appeared? Please share your reviews if you've actually received the procedures! I'd prefer reviews for treatments that aren't too expensive. Also, even if it's not a procedure, are there any good ways to prevent melasma and blemishes from forming? I've noticed that improving lifestyle habits is important. Of course, I am diligently applying a serum containing Vitamin C to my basic skincare routine!