Most spreadsheet applications have built in formulas and functions that will do the math for you so you don't have to. You can keep a running balance of your accounts and you can have each category totaled as well. You can keep it as simple or make it as sophisticated as you please.
You may want to create a workbook with multiple sheets for various aspects of your budget. You can have one sheet that keeps track of savings and investments and another sheet that lists your monthly bills.
Spreadsheet templates are used for many reasons and each template vary according to the purpose it is used for. Spreadsheets are designed with different calculations depending on various needs.
You could make money doing something you love (or like [or maybe not so much but just really good at]). It's great to see a spreadsheet come together, and usually a lot better than what you originally envisioned. Especially when the dang thing works.
spreadsheet templates for business
what is spreadsheet in excel