I was just wondering if anyone could tell me a good exercise for practicing dexterity. I can’t seem to do two different things at once with my hands.
You need to actually play the piano to develop those muscles and the neural nets in your brain that correspond to them. The Czerny piano finger exercises are excellent but if you don’t read music, you will need to have someone show the exercises to you on a keyboard and memorize how to do them. In the meantime, start learning to read music-it is a skill you can use with any instrument and with singing.