aspire to mastering calculus and real analysis by working through good textbooks?
Can a person with a weak background in math

Well, I am only worried about the math skills for the sake of knowledge, not for the sake of acceptance in good PhD programs.
I believe that it is too hard a path. You will need some sort of endorsement that you have these skills, and that can only come from grades afaik.

I intend to specialize in macroeconomics, primarily in DSGE models, along the same lines of Larry Christiano
https://faculty.wcas.northwestern.edu/~lchrist/course/AEA_2018/syllabus.htmlYes but to what end?
Not a rhetorical question, what's your end goal?
Lmao 1995 called, it says you should go back there

If you have to ask on EJMR, it is surely too hard for you. Also, considering you ‘just want the knowledge’, it sounds like a hobby. 99% of macro economists outside of theorists just use the models in an applied way. Some deep understanding of the abstract math behind why their models conveniently converge to unique allocations is not required.
Just take Khan academy for it rather than some textbook. Real analysis isn’t that important if you can follow a logical argument. That’s all it is, really

Not a hobby
Not a hobby, but a means to understand DSGE models well.
Don't HANK models presuppose knowledge of advanced math?If you have to ask on EJMR, it is surely too hard for you. Also, considering you ‘just want the knowledge’, it sounds like a hobby. 99% of macro economists outside of theorists just use the models in an applied way. Some deep understanding of the abstract math behind why their models conveniently converge to unique allocations is not required.
Just take Khan academy for it rather than some textbook. Real analysis isn’t that important if you can follow a logical argument. That’s all it is, really