What budget you want to use, Financial Budget, Sales Budget, Purchase Budget?
If you want to use financial budget, you can view a summary of the amount budgeted for each G/L account in different time periods and if you have not yet set up your budget, you can fill fields with budget for each account.
You can select different time intervals by clicking the buttons in the lower left-hand corner of the window.
You can set what you want to see in lines and what in columnes.You nedd to fill values in matrix fields.
All of the and more of then, you can read in manual or help. You must to know what is your requirements.