Lunch, Meeting
Lunch is something different to obiad, you can have lunch and still have obiad at home after work - so no it's not an unnecessary borrowing
Meeting - you need two polish words like 'spotkanie załogi' 'spotkanie pracowników' - meeting is not a generic word like in English it has a very specific meaning when used in Polish
btw there is a word mityng in Polish too, which also comes from English meeting - it means more or less rally in English 'mityng wyborczy' - it was introduced to Polish already before the II WW
fast food - does not have an equally handy and equally specific term in Polish - szybka żywność - very awkward, szybkie żarcie - good but too colloquial (English term is not slang), szybkie jedzenie? - too ambiguous (jedzenie can be both eating and food)
as for geographic names - those names that are polonized are declined - Nowy Jork, w Nowym Jorku, do Nowego Jorku, w Londynie, do Londynu
some names that don't look polonised are still declined - Montreal, w Montrealu, Halifax, w Halifaxie (though w Halifax is also correct), Quebec, w Quebecu (though if we talk about the city of Quebec I would rather say w Quebec), Lyon - w Lyonie, Zurych (somewhat polonized) w Zurychu), Manitoba, do Manitoby, Saskatchewan either w Saskatchewan or w Saskatchewanie, Alberta, do Alberty, w Albercie, Labrador, na Labradorze (it's na because it's a peninsula), na Labrador), Ottawa, w Ottawie, do Ottawy