Hi @CGuevara,
To preface, I’m assuming you’re using the Envelope Budget. Are you talking about adding the formula to your main budget sheet, where it shows your budget for the month? That sheet is a dashboard and all of the data in it is all generated by some complex formulas, I really wouldn’t recommend changing things there.
I know it may take some effort to switch, but I’m a big fan of the Savings Budget, which you can find out more about here: Add the Savings Budget sheet
It has nearly all of the functionality of the Envelope Budget, but it’s based on the Tiller Foundation Budget. In this template, the Categories sheet shows your budgets for every month all in one place. This is where it is easy to use formulas to calculate your budget like you’re trying to do. I’d encourage you to check it out!