Sounds like you say you want or need to spend less than what is actually available to spend. There's a few ways to approach it. You could indicate that you want to spend some percentage less than 100% of retirement assets. At some point, if you choose a percentage too small, the program will impose RMD, so you can't leave it all on the table.

You can also just not spend it each year as you go forward and your spending amounts will go up and up each year as you keep pushing unspent money into the future. There's no harm in that, but it sounds like you are less interested in the question, "do I have enough spending available? or How much can I spend?" as you are the question: How much will I have left over if I spend less than what I can spend?" If it's this last question, you can also enter a special expense at the end of life and through trial and error raise that amount until the amount of annual spending drops to what you think you will spend.