I can't help with the Japanese, but can give some feedback on the English.

First of all, your English is very good. Most of it has no fault, but there is a typo at the start of the soy sauce paragraph which you'll probably see straight away (just a letter wrong).

This is the only sentence which confuses me:

"Dashi (broth): Dashi is that kelp, bonito flakes, or dried sardines are boiled in hot water and brought out the flavors of the ingredients."

I will write what I think you're trying to say:

"Dashi (broth): Dashi is kelp and bonito flakes or dried sardines which are boiled in water to bring out the flavours of these ingredients."

It's interesting that most of these seasonings are fermented. Something we don't use so much in our western diets.