Buying ETFs as Italian citizen living in Japan?

Hi everyone! I just started a new job and moved to Japan, I'm looking forward to contribute to this sub as I recently started developing a passion for finance.

My main question is if and how I can buy ETFs from Japan paying in yen. Ideally I would like to invest ~20% of my salary.

I would like to keep it as simple as possible in the beginning, investing in either world or SPX-like ETFs.

Do you have any advise for a beginner like me? 🙂