Budgets is an interesting app because it allows you to plan your budget and any deviations for each month you have chosen for your budget period.
You can navigate Top Down and Bottom Up, i.e. from the general to the individual and back. So you start from your Budget Object, in which you set the Budget Period, and in Navigate to Months you can see all the Months created for the period. Select a Month and navigate to the Categories like Car, Vacation, etc..
In these Categories you set the Budget for the given Month.
and within the Category you can create Expense Entries.
For a Refresh of the Data you can pull down the List.
On the top Level you can select a Budget and tap on the Menu on Chart. to get a graphical Overview.