I'm curious about how to whiten my face. What methods are effective?

After summer passed, my skin tone looked dull overall, so I'm really curious about how to make my face whiterㅠㅠ
Even though I apply sunscreen every day, my skin looks darker after summer because of freckles and blemishes.
So, I searched the internet for ways to whiten my face, and it seems like vitamin C ampoules, whitening creams, and sheet masks are good. Has anyone actually seen any results? I'd like to try simple home remedies first, rather than procedures. If you know of any good products or lifestyle tips, please let me know.
I would appreciate it if you could share how you manage your face whitening:)