I'd like to list expenses by categories (drop down) - and then a total of each category

I'm working on making a monthly expense report with 2 sheets; the first sheet would include each individual expense and the expense would placed in a certain category. The second worksheet would be a summary of the total expenses for each category.

I would like column A to be a drop down menu:
Column A: Expense type (Stationery, Kitchen, Maintenance, etc..)
Column B: Amount
This would continue for as many rows as i need

Then on a different worksheet it would add each item based on its category and give a total for each category.

Thanks in advance