Herkfsu,
I don't think spindr0 is picking on you when he corrects you. With options is is important to learn the language of the product. If you buy a box spread, you buy the vertical call and put spread. If you sell the box spread, you do the other side.
If you buy any 10 point box for less than $10, your profit is the difference between your net buys and the 10 points minus any expenses and interest. If you sell a 10 point box for more than $10, your profit is the difference between that credit and the $10 you get at expiration, if you get to keep that to expiration. If this is not a cash settled index, and the spread is trading over $10, there are a number of situations where you can lose money from early assignment of the ITM put or call.
Bob