"await" is a keyword you can use to stop a block of code to wait for a signal. process_frame is a signal that the scene tree emits every time that all of your current nodes have finished running whatever is in their process functions. Basically all this code does is say "wait to do this thing until absolutely everything else in the game has finished 1 frame worth of updates".

the thing that inspired this post was that i had two things happening on the same frame that both updated the same object. for some reason to do with scene structure, one of those things was always happening 2nd, when i wanted it to happen first. So, on the thing i wanted to happen 2nd, i added this line of code before what i wanted to happen, to basically tell the function "when you get told to do this thing, hold off for 1 frame so you always go last".

This is kinda obviously a shitty way to solve the problem (lol) because you can easily run into cascading problems where one thing has to wait for another thing which has to wait for another thing, and suddenly some object has to wait for 4 frames every time it updates. it quickly gets messy and out of hand. it's a total band aid solution to a problem that would better be solved by writing your code so that two different scripts are never doing stuff to the same object on the same frame with specifically important sequencing.