I originally walked out of a step of 14, and thought it was obviously too much, which was not the correct answer.

But judging from your answers and comments, step 14 is rare, as shown in the figure:

According to the operation, the formula is: ((2019+7) ÷ 2+7) ÷ 2-5-5)-5) × 3× 3-5 = 2020.