Each song has 5 different Dance quests to complete.
For example: get 3 stars, get 4 stars, perform all Gold moves etc.
You can check for each song what you have to do by selecting the song first then swipe down to reveal and select the dance Quest checklist. It will show what you need to complete.
EDIT: It seems it's not locked to 1 specific song the quests and they accumulate over any songs you do. Once you have completed 5 individual dance quests in total the achievement will unlock.
Thanks to Pinicus for this info