I'm trying to see if there is a code for this pattern.
I'm looking at having a stable white RGB led light and then push a button and it very slowly fading to a
Stable blue light and stays on unit I Press the button again and then goes back to white.
There is no code until you start to write some. Start with some simple beginners tutorial. Your project shouldn't be too hard to realize.
White = Red/Green/Blue (255,255,255)
Blue = Blue (0,0,255)
You're fading the red and green between 0 and 255.
The Arduino IDE comes with enough example sketches for fading and button use that if you work your way through them, you can alter them into what you want.
Figure out how to use that, at least give it a try, then come back when you need clarification.