A few inaccuracies in the vocabulary here and there, but nothing major.
sur les marches -> that's real steps, i.e. the stairs leading down into a métro station.
Lorsque je vis Paris accaparant des rues -> I'm not quite sure what that means, but my best bet would be "when I experience Paris and its clamorous streets", except that would rather be "le Paris..." as in "the clamouring aspect of Paris you experience in the streets". That's pretty bad French anyway, in my opinion. Far too lofty and ambiguous.
Actually the sentence begins in the last line of the previous paragraph:
I feel proud of my solitude
dummy line break
when I experience whatever clamorous streets
and life in the city blah blah
where you have to do such and such
in a so and so struggle. Phew, that's it!
Devant... Jamais ! -> that makes no sense whatsoever.
It's hard to make out what she sings, but my bet would be "au grand jamais" ("never ever")
Also it could be worth mentioning to English speakers that it's a man speaking, despite the female singer.
_k.o.a 🇬🇭