I'm really worried about melasma and blemishes. What kind of treatment would be effective?

I've been working outdoors a lot lately, so the freckles and blemishes on my face have gotten much darker, and it's really bothering me.

No matter how much sunscreen I make sure to apply, once a breakout appears, it can't be covered up with makeup and actually gets darker.

So, I think I need to get a treatment before the freckles and blemishes spread further.

Which procedure would be effective?

Besides procedures, would things like melasma removal creams be effective as well?