Your translation is possible but not better than the official one. Just my opinion.
To me, ❛Which place is this?❜ would seem natural in English if someone was driving around and wasn't certain where they were, for example.
Why is it कौनसी and not कौनसा ? Can anyone please tell the difference between these two?
It's कौनसी because जगह is a feminine noun.
कौनसा is the masculine form and कौनसी is feminine.
Oh I get it well जगह is a word which means place and thus generally places are considered feminine in Hindi , am I right??
Every noun (both common and proper nouns) has a grammatical gender in Hindi. But just because जगह is feminine does not mean that all places are feminine (for example, भारत is masculine while दिल्ली is feminine). Moreover, स्थान which also means 'place' is a masculine noun.
That said, you can sometimes guess the gender of a word based on the category. For instance, most country names are masculine, most river names are feminine etc. But there are a lot of exceptions to each of these rules. The same is true for guessing gender based on word endings word (words ending with ा are more likely to be male, those ending with ी are more likely to be female etc).
The only foolproof way is to learn every new noun that you come across along with its gender (i.e, instead of memorising dog=कुत्ता and cat=बिल्ली, you memorise my dog=मेरा कुत्ता and my cat=मेरी बिल्ली ).