Suggested edits are in brackets [like this]. I'm a good-hearted kind of guy. I like studying languages and [improving] myself. Lately I feel a bit under the weather and frail[.] I'm an [emotional] person and sometimes I'm overwhelmed by things. I've been studying Japanese for 3 years but I still can't speak it very well. I noticed Japanese people tend to be kind to me because I behave more like an Asian guy [even though] I'm European (Italian). I'm looking for a spouse in Japan. I want her to be very kind and [well-rounded], that's all. I've already been to Japan once for 3 months and am planning to go back there in a few months. I like hot [foods or weather?] and warm people. I disagree with Matthew that "warm" is strange here; I think it's fine. Otherwise his suggestions are good ones.

"improving myself" "emotional person" "even though I'm European" You could say spouse or wife Comprehensive isn't really a way we describe women haha what do you mean by that? saying you like hot things can have a weird connotation Spicy is better warm is ok but a little strange in the context I see what you were aiming for one way to end would be: I like hot spicy foods and warmly kind people