Also you might consider to start some music playing for developing your fingers. For me playing vertical piano was kind of another step in mastering my keyboard skill because it involves all 10 fingers and vertical piano is significantly harder to press than grand piano or (especially) a synthesizer.
Your ring index issue looks very strange for me. I have noticed that nowadays nobody press a door bell button with ring finger anymore, probably because of smartphones.
add: If this is not obvious from my comment, I want this to be obvious: download any keyboard training software or use this kind of website. Requirement is an ability to start from 4 letters.