If the flame waves, hisses, shrinks, spins, widdershins, or left to right like I'm shaking my head no, or goes out it means no to your question. These are negative responses.
If the flame grows tall, stays calm, moves back and forward like I'm nodding yes or spins desolate, it means yes to your question.
At the sign of a spirits presence it will come alive and try to burn you when you try to touch the flame. If ott grows tall and has a blue tinge, a spirit is present. Two flames on one wick means two spirits are present.
It can have numerology correspondences like for like to your question. 1 flicker: yes, 2 flickers: no or represent how many years to your question. For the advanced at using these correspondences, also communication with spirits is best done on Wednesday with a blue candle, love questions on Friday with a green candle, all divination with a white candle on full moon.
My candlemancy spell gaze at the flame, 3 minutes and look away, see the light that remains. It will change color according to your question and shapes.(Green, orange, blue, yellow, white means yes, red, purple, black, grey means no). Observe the candle's flicker, the shapes that form also have meaning. A skull means death, a heart love, a face the person or spirit etc.
I hope this helped. Bright Blessings )O(