how do I remove the spare tire from a2007 toyota sienna
It does not have one - the Siennas have run-flat tires.
Not on the underside. A full size spare would be too close to the ground to be practical.
In Sienna 2006, spare tire is below the 2nd right seat.
check it in the internet and i have no idea
under the car in the rear
There is no space for a spare tire if you have AWD. That is why factory provides the Run Flat Tires.
It is located underneath the vehicle in front of the right rear tire.
what is the part for lowering the spare tire on 2004 nissan frontier
Yes, of course, it can fit in trunk.
The spare is under the van, between the front seats.
If you have the Limited (aka XLE Limited) trim level then it was factory equipped with run-flat tires and there is no spare tire.