I get a job in Japan. What’s next?

It’s my first time moving to another country, so I need a lot of info.
Any considerations before leaving my country?
I’m open to read all your suggestions.
Also experiences from couples (is it easy to work with spouse Visa?)

https://www.reddit.com/r/japan/comments/128qjv3/i_get_a_job_in_japan_whats_next/