“Can anyone correct this sentence?” English switches the order of modal verbs and the subject in questions, remember.
Now, in the American English I know, if we are talking about the general idea of parks and areas with grass and things within cities, we would say “green space” as a mass noun.
Green space gives me hope.
If you sort of mean that green space is good for your mental health and makes you feel better, maybe say that. But it depends whether you mean that or something else.