Breathing for singing is different than for running or dancing. Relax the lower belly completely. Your lungs are now full even though you didn't hear the noisy inhaling process. Force the air up from the bottom of your belly, pushing your diaphragm wall outward in front, on the sides, and in back, leaving your chest, neck and face completely relaxed. This is the beginning of beautiful, flowing tone for any style of singing.
Accurate pitch requires maturity and control over the voice.
Listening is the basis of all musical skills. Learning musical notation is much easier on an instrument. Piano is an excellent beginning instrument. Developing the voice is a challenging, life-long process. Don't force your voice.