What does a day in a Japanese school in Japan look like?

I'm 41, I've been learning Japanese on and off for a few years. For the past year and a half I've been practicing on Anki, and I recently started classes with a Japanese teacher, with whom we're going through the Minna no Nihongo lessons.

As a personal challenge for myself, I'd like to save money for a few years and go study in Japan for six months or a year. My learning of Japanese is a personal project, unlikely to have a big impact in my employability or salary. I should also mention I'm not married nor have kids, so those commitments wouldn't be an issue.

So, my questions:

1. To the point where it's possible, how would you describe a day in a Japanese school? Is it mainly conversation, writing, or a mix of everything?

   1. How much time on average would you say it's needed each day (on top of the classes themselves) in order to stay on top of things?

2. Apart from the classes and study, what other activities (that can't normally be done outside of Japan) would you suggest to maximize language improvement? I've already visited Japan once and went to the main tourist spots, so sightseeing isn't a huge priority for me.

   Thank you very much for your help, and apologies for the long post 🙂