First time traveling to Japan. Any advices?

Hello all! I'm planning a Japan trip in the latter part of the year for 2 (me and my gf). We love sight seeing and culture-rich things to take part in and we don't mind a bit of walking. We're flying from Ha Noi and our budget is around 1k usd each. I'm looking for advices and recommendations. Everything is much appreciated. Thanks in advanced!

I'm not expecting detailed answer or full-on guide. Just something thats on top of your mind and i'll start digging

by Forward-Paper5829