Sorry, when I say "I am interested in Italy, Germany, Japan and France" I mean I am interested in these countries because of their language, history, culture, etc. I am fascinated by these countries / I really like these countries / etc.
Grazie in anticipo !
You could say, "Mi interessano l'Italia, la Germania, il Giappone e la Francia."
"I am interested" literally means "sono interessato/a". Remember that in English you use the preposition "in", whereas in Italian we use "a". "I'm very interested in English" = L'inglese mi interessa molto / Mi interessa molto l'inglese or Sono molto interessato/a all'inglese. (I feel the former option is better.)
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