No, for singular, countable nouns you need to use an article (either "the" or "a/an").
Yes, there are no articles in Polish and there is only one present tense so there are just many ways to translate it to English. E: As freymuth says, it's alright except grammar mistake in your English sentence.
Actually, that's not correct. Although Polish doesn't have articles, English requires them often for a sentence to be grammatical. See here under the subheading "Articles" to see what the course mods have to say on the topic. Articles are often not needed for plural nouns and uncountable nouns, but they're normally necessary for most other nouns.
Of course they are required - in English. I've just written that there are not any in Polish language and of course they are necessary for proper translating correct Polish sentence (without articles) into English (with articles). You just elaborated what I said. I answered only if the meaning of this sentence is identical in Polish and English, I can't give any advice on English grammar.
Sorry, it looked like you had said "Kid eats bread" is a correct translation, which is not the case.
Yes I'm sorry either, it could look like this because I didn't focus enough on the side of grammar in English sentence (also English is obviously not my native language). I need to try to help much more carefully.
Well, I think 'baby eats bread' is a reasonable translation... it's quite common to form sentences like this where 'baby' in the noun. Still, some useful information on this discussion.