Do more is what you want, buy at a low price, and then sell at a high price to make a profit;
As for shorting, you expect the price of gold to decrease. Even if you don't have anything on hand, you can sell it at a high price first, and then buy and close the position after it falls to a certain price, so there will be gains.
As for the trading you mentioned, it is certainly possible, because in essence, your trading method is long, paper gold is T+0, and you can trade many times a day.