Butterflies are common patterns on flowers, representing beauty, happiness and prosperity. This pattern has no influence on Feng Shui, because it is only an element in art, not a real Feng Shui symbol.
In geomantic omen, some factors that need to be paid attention to include the orientation of the house, the placement of furniture, the position of doors and windows and so on. These factors may have a certain impact on the household's fortune, but it does not mean that you can draw patterns on the wall at will.
Therefore, if you are interested in Feng Shui, you can learn some related knowledge, but don't be overly superstitious about Feng Shui, and try to create better living conditions in real life.