Tbh it does look a bit "tired", for want of a better word. Many pet store plants are in poor condition (& overpriced), which is why I've completely switched to buying online. But that's beside the point. The fern in the photo is not 100% healthy, but I can see new shoots under the old leaves so that's certainly a good sign. If I were you I'd remove the worst affected/oldest/most damaged leaves and leave as many healthy/young ones as you can. Under the right conditions it will bounce back and get a nice lush green colour.
Note: Some browning, especially on the tips, is a normal sign of aging. Not a problem at all.