Typing Numbers

hello guys , i am a beginner typists and i type only about 28 wpm on average , I have a question that might not even be a valid one . the question is :should i isolate each finger when reaching for further keys like numbers for example? , especialy with ring fingers , I noticed that in order to reach for keys like X , 2 , 9 I can't help but move the pinky with it , please help me on this one , and thanks