What do you think of your new neighbourhood?

They are both good and mean the same thing. You wouldn't have to worry about it having a 'lost' meaning. They are the most commonly used questions in USA/Canada for this situation. Spelling mistake in 'your' not 'you'

You could say "How you find your new neighbourhood?" in this context if you wish, it's more of a colloquial way of asking the question. The meaning of this sentence depends on the context of the conversation, so it could also mean how do you find it when you are lost, however, I think in that instance I myself would use "how do you get to your new neighbourhood" or " how do you get to your new neighbourhood from ...(specific place)"

How do you find your new neighbourhood? (it is correct, it doesn't change the meaning) number 2 is incorrect. it needs "do" in the sentence How do you like your new neighbourhood? What is your new neighbourhood like? Is your new neighbourhood.....