A note about "do domu" = "home / homewards"
"dom" is a masc. noun ("mój dom") "do" is a preposition, which always takes the genitive case: "do" + gen. = to, up to, as far as, until
we put "dom" (masc. sing. nom.) in the gen. The endings are "-u" for inanimate and "-a" for animate. Therefore "domu".
-> "do domu"
Yes, hm, I will try to explain it. When you say "chodzę" it means it's your routine. "Codziennie chodzę do szkoły" (I go to school every day). "Co tydzień chodzę do sklepu" (I go to a/the shop every week). But if we're talking about home, it's always "Wracam (I return) do domu" or "Idę do domu". No matter if you decide it in a specific moment ("I'm going home!"), or if you're telling someone about your routine ("Every day after uni I go home" - "Codziennie po szkolę idę/wracam do domu.") - better use idę or wracam than chodzę. I hope it's more or less clear ^^
"Dziękuję za odpowiedź"
This is a new phrase for me, thanks! I've noted it down (I hope it's correct lol).
Analysis: odpowiedż = answer (nom. sg. fem.) za is a preposition with three forms (+acc., +gen, +loc.) here the one of interest is:
za (+acc.) = (to) behind, beyond; for, in exchange for
noun declension endings for nouns in acc. of fem. sg.: hard stem = -ę soft stem = nothing
therefore: "za odpowiedż"
Why is the answer on the other page "I'm walking the house" Then on this page the translation is "I am going home." I am walking the house sounds like you are taking the house for a walk which is not possible unless it is a doll or dog house. If it is "I am going home" then the translation on the other page is way off.
In general "iść" (there is also an accent over s) is used for going/walking right now and "chodzić" for habitual, repetitive going/walking. Read also discussion above, there are examples and explanations there. Read the tips to this skill https://www.duolingo.com/skill/pl/Verbs%3A-Present-2/tips-and-notes