1. It turns out that a futures contract is only established when one party buys and the other party sells. People who look in the right direction earn money from people who look in the wrong direction. What you said is existence.

2. Closing positions corresponding to buying and opening positions are selling and closing positions.

Closing positions corresponding to selling and opening positions are buying and closing positions. The principle is to use positions in different directions to offset each other and earn the difference.