I have not been to Japan other than Narita Airport.
I suggest a little reading to gain a little insight to those that you will be seeing and interacting with in some capacity.
The Culture Shock series is a very good one and they have many different cultures in the series. I am a bit biased since I first read a copy of one of them handed to my by the author, my uncle when I was a teen. It helped shape that knowing the differences of cultures help remove simple interactions from being interpreted as "rude."
enjoy your trip.
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