。
I'm too busy for that.
Literal
Busy-[て] that-situation [not-じゃない] [emphasis-よ].
それどころじゃない is a set expression meaning 'this isn't the time for that' — literally 'it's not even that situation/place.' じゃない is the casual negation of だ. よ adds emphasis. Very natural, colloquial way to brush off a topic or request because something more pressing demands attention.