When it comes to leading versus being in the choir, you are not blending anymore. you can now hear everything that you are doing with and to your voicel more clearly. Befor leading a song make sure you are well warmed up. There is no problem with changing the key if needed.
In terms of your range, find the best way to approach your higher notes. For most, working our way to higher notes is best but for some hitting a higher note and coming down is better. Do not try to be like the artist. You do what you know your voice can do comfortably. start on a C3 and slide up an octave without breaking. keep going up and in different keys. As your voice slides, let it go to whatever resonant area (head, chest, falsetto, or head mixture) it needs to. Practice that for awhile and vary the pattern trying to do it with runs. The key is to not try to chest everything but train your voice to seem as though it is. Anymore questions regarding this, feel free to message me.
