Which pitch to use?

When doing the warm ups and others and following the piano you press a lower key in the piano and a higher key on the piano before doing the melody. When trying to start off on the high note I end up not being able to go very far. But when I start off on the lower note you play on the piano I'm much better 

am I doing this correctly?

i hope this made sense 

stay safe everyone ! 

Hey Danny! The lower octave is for male singers or singers with lower ranges. (Some higher-voiced tenors could sing along in my octave). Use the range that works best for you!