No one will know when you will be able to profit. Even when the market is good, you can find it difficult to make profits because of greed to take more profits. So it is highly not recommended to borrow money to start trading but if he is really confident in his ability to earn profit, he can try it for a week.
I suggest not taking risks that you may not be able to afford. But if you are able and confident, just try it.
If they are already working and have a salary, maybe that will be okay because they can set aside part of their salary to pay off the loan. But some still have problems because of the necessities of life that they have to fulfil.
After all, if they lacked expertise in trading, it would also make it difficult for them to make profits. We recommend that before they decide to take a loan, they can calculate everything, including the risks.