My skin has become tanned and dull ㅠㅠ Can whitening products fix this?

I've disliked sunscreen since I was young, so I didn't really wear it.

Now that I'm 27, my skin looks dull and it seems like aging has started. (Atopic dermatitis treatment: It got darker while receiving phototherapy.)

I am trying to get into the habit of applying sunscreen now, but will whitening products restore my already darkened skin?

As my skin tone gets darker, it feels like my hair color doesn't suit me either.

What should I do? The photo is lacking and the difference in facial skin tone is too severe haha...

It's stressful.