1. Futures is a zero-sum market, and the futures market itself does not create profits. In a certain period of time, regardless of the transaction costs of capital entry and exit, the total amount of funds in the futures market remains unchanged, and the profits of market participants come from the losses of another trader.

2. Many websites have basic books about futures. I recommend two books to you. Futures operation and technical analysis of futures market. I feel good.

I don't quite understand this question. If you close your position, the ups and downs have nothing to do with you. If this product rises again after it is sold, it will definitely be a loss if it is not liquidated.