How do I apply an old budget to this year?

I just got around to creating a budget, and used data from last year as a guide as I did it. To do that, I had selected 2021 in the annual view and adjusted all the category balances. When I click the right arrow to go to 2022, the total spending number is significantly different - i.e. it looks like it's referring to some old numbers inherited from somewhere. I've seen other guides how you can come to the end of a year and create a new budget for another year using this years settings. But I can't find any of those options. Is there away to force the 2022 budget numbers to be inherited for the budget I created for 2021? I hope this makes sense. I've duplicated the budget - can't figure it out. I created a new budget but that seems to ask me to start from scratch. I can't figure out how to preserve all the work I did for 2021. I'm not sure where the numbers are coming from for 2022 on that same budget, but the "spending" target number is wildly different from what I have for 2021.