This line is from Diary of a Wimpy Kid #2:
After all those years of getting pushed around by Rodrick, I was definitely ready to move up a notch on the totem pole.
But Mom and Dad have always been super protective of Manny, and they won’t let me lay a finger on him, even if he totally deserves it.
A Native American totem pole is a carved pole with figures stacked one atop the other:
The presumption is that the more important figures are near the top. Being "low man on the totem pole" is a familiar American idiom, meaning being at the bottom of the organization's tier of importance. "Moving up a notch on the totem pole" thus signifies an increase in importance.
As defined by the Cambridge online dictionary, being the low man on the totem pole is "someone who has the least important position in an organization". In the example you show, the organization would probably be the social network surrounding the wimpy kid. The dictionary goes on to show an example of how someone can start from being a low man on the totem pole and "work their way up to become a manager". I.e. moving your way up the totem pole is increasing your standing in a given group.
You may also find these related questions regarding men on totem poles interesting:
Not sure of your source but it is an improper combination of the two terms, "Taking it up a notch" and one's position on the totem pole. It is easy to see how the two could be combined. The use of the "totem pole" to describe one's position in an organization was made popular by H. Allen Smith in Low Man on a Totem Pole (1941). The totem pole has been used to represent class or business structures and one's regrettable position ever since.
Take it up a notch is best described in https://english-grammar-lessons.com/take-it-up-a-notch-meaning/
‘Take it up a notch’ is a common figurative saying in the English language that is usually used to mean that something or someone should (or is going to) increase their performance or capacity.
This is the answer to the question posed. Again one can see where the two would be joined up in common usage.
This is crazy whitewashing of actual terminology. Generally the more important carvings on a totem pole are at the bottom.
Well, the totem pole is a euphemism for the food chain, which is a euphemism for the social ladder. Ergo, the notch is really a rung, or step. Thus the meaning is something like "Those who naively thought that this person was their equal might want to start getting used to the idea that he or she will soon be their superior, joining the ranks of those who habitually make their lives miserable, their aspirations laughable, and their opinions meaningless."
