Hey @michael303,
What @aronos is saying is all spot on. The Savings Budget is definitely worth a look and it is fully compatible with the Foundation Template. It references the same budgets in your Categories sheet as your Monthly & Yearly Budgets do. And you can run the Savings Budget concurrently (i.e. with the Monthly Budget) in the same sheet.
At this point, I highly recommend this path rather than the envelope budget as our team can better support the new tool. The Envelope Budget is great but is overdue for an update that aligns it to our current best practices.
Just keep in mind that if you run the budgets concurrently in your Foundation Template, any change to one budget affects both— they are not independent tests…
Good luck.