I can't see any white spots but I can see clamped fins and excess mucous on their body. The excess mucous gives them a creamy white appearance over their body and fins.
Excess mucous is caused by poor water quality or something irritating the skin (possibly chemicals or parasites).
If the fish have small white spots that look like grains of salt, then post another picture that shows the spots.
Check your water quality for ammonia, nitrite, nitrate & pH?
Do a 75% water change and gravel clean the substrate every day for at least 1 week or until we work out what is going on.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.
----------------------
If they do have whitespot (I don't think they do), the safest treatment is to raise the water temperature to 30C (86F) and keep it there for 2 weeks. You won't need chemicals because the heat will kill the parasites.