“It's not up to me; I'm way too far down on the totem pole.”
At work, a member of another department suggests a change. You think it's a good suggestion, but you can't agree to it because you don't have the power to make the change. One of your bosses will need to agree to it. You say this.
It's not up to me; I'm way too far down on the totem pole.
You can say that a decision "is up to" a certain person. This means that this person gets to make the decision. For example:
A: What do you want for breakfast?
When you say "it's not up to me", it means that you don't have the authority to male a decision; someone else has to decide.
A "totem pole" is a large wooden pole with shapes of heads cut into it. The heads are stacked on top of each other. Totem poles were originally carved by native tribes in the northwest region of North America.
These days, it's common for people to compare a business organization to a totem pole. The person in charge is "at the top of the totem pole", and ordinary workers are "at the bottom of the totem pole".
Describing someone as "___ on the totem pole" is casual but not too casual. It can be used in some formal situations too.