Under vehicle settings in the MID, select Fuel Economy. There you can choose between lifetime, per tank, or per drive.
Quite possibly true, but I have not tested it on my 21. Pretty much always have it set on Tank. I have found that on other Toytotas (2022 model year) that when you hit the Update button on the Energy screen on the Head unit display, it also resets the fuel mileage when in Total mode (not really sure what the label is).The setting for TOTAL doesn’t appear to be lifetime. My understanding is it resets in conjunction with the trip odometer. Happy to be corrected here if mistaken. I use TANK average anyway.