Funds can make money or lose money.
For a very simple example, you take 1000 yuan and buy it when the rice is one kilogram in 2 yuan, and you get 500 kilograms of rice. When rice 3 yuan rises to one kilogram, 500 kilograms can get 1.500 yuan and earn 500 yuan.
To buy a fund, 2 yuan is the net value of the fund, 500 Jin, which is the share that you spent 1 1,000 yuan to buy. When the net value is higher than that of 2 yuan, it will be earned when it is sold, and it will be lost when it is lower than that of 2 yuan. That's how you make money.