It is very hard to understand what you are saying, so I'm sorry if I'm unable to answer what you are asking, as I'm not really sure what it is that you are asking.
Don't listen to what people at the store say, most of them have no idea how to tale care of a betta fish. Do you have a thermometer? What temperature is the water right now? Bettas need to be in water which is at least 78 degrees, anything less is too cold.
If you tank is not even a gallon in size it is way too small for a betta fish. You need to buy a bigger tank, one that is at least 2.5 gallons in size. Bettas do not like living in small spaces (would you like living in your closet?) The fish would be much happier in a larger tank.
On water changes: since you have no filter in this tank and it is way too small to cycle anyhow, you need to be doing at least 50% twice a week. The same will hold true with a 2.5 gallon tank.
Color wise it is difficult to say with this picture as the flash glare is right on the fish. But he looks like your average pet store blue betta with a red wash. Beauty is in the eye of the beholder. If you think your fish looks pretty, then he is pretty.