need help plz. the only guide in this site doesnt tell me what i want. dont get angry if what i say doesnt make sense lol

im trying to make a karaoke file. ive never done this before so im quite clueless. i have the video, the mp3 song file (320kbps), and the instrumental version of the song file (mp3, 320kbps)

what i want to make is a karoke with subtitles (colour flowing through the words if not too hard) and with left and right channel (i think its called that), how u could press a button and change whether or not there is the singer's voice

i know most ppl use audacity to erase the singers voice but i was wondering since i have the music only file, if i could use that for the left/right thing instead since it will be better than the music only made by audacity