My strategy is not to exceed the loss threshold in gambling by making a maximum deposit of 20% of my savings to enjoy the game, and when the balance runs out I must stop so it doesn't have a big impact on my finances.
20% of savings is already big imho That's a huge part of savings for someone supporting their family, but the word "savings" is what caught my attention here, see, not "earnings", but "savings". I think it means the guy is living with his parents, saving little by little from what he's getting for small expenses. I may be wrong of course, but then the guy should probably reconsider his budgeting. Spending 20% on gambling is unacceptably a lot.
It could be the situation that he still lives with his parents and saves little by little. But I think if depositing as much as 20% of his savings just to enjoy gambling, I don't think it's wise because he can forget to control how much he spends. A total of 20% of the savings is for one-time use or several times playing gambling would not be recommended to use that amount for gambling.