I am a 10th grader and I am looking for a journal/review to publish my paper in the subject of macroeconomics. Is anyone aware of any journal/review that would allow me as a highschooler to publish such a piece?
This is possible. And any journal, in theory, will accept your work. However, I think you should seek out some feedback from an economist in the related area. Also, it is an unfortunate reality that econ journals are very 'clubby'.
As an aside -- i am a PhD student studying macroeconimics. If you want to try and provide some idea of what you're doing, I can try to give you advice about journals etc. And feel free to be however vauge you think you need to be to protect your idea.