Learning vocal means that you need to understand the correct phrasing of a musical passage in a song, sing the right part in the right rhythm or cadence, and fit the song with the correct melody. If you're one of the main singers in a musical performance, you should learn to do all the right techniques for creating a good vocal.
Learning how to enunciate well while singing a melody is one of the key characteristics of a good vocalist. Another way to do a great vocal is to put yourself deeply into the emotion of the musical piece and give everything you have into the microphone. The emotive power you pour out into the vocal will resonate well when heard live or heard in a recording.