Unfortunately for you, there are no clear-cut answers to your questions, as everyone has different preferences as to which language to use or which engine to make a game in.
Fortunately, someone has made this helpful guide to answer many of your questions.
If you still have questions after reading through that, I'm sure the community here would be glad to point you in the right direction, but you'll find that most of what people here will say is echoed in that guide.

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