Hello Guys! I really need your help!

I sing opera and i am a lyric Baritone.
I' ll be recording lots of things as a Baritone and i really don't know how to do it but i know it's a little complicated.I have recorded rock,metal,pop stuff before but i know that this is a lot different.

I know, you're supposed to record opera singers in acoustically perfect concert halls, but I'm on a budget and all I have is my 8 x 10 home studio which doubles as both a control room and a live room. My goal is to record live vocals over pre-recorded orchestra karaoke tracks to famous soprano arias.