1) Hindi ako masyadong marunong mag-Ilocano.
Hindi = no/not/do not; masyado = too much; marunong = to know/to be knowledgeable; mag (we affix these to the name of the dialect to indicate speaking it)
2) Kababalik ko lang galing America.
Kababalik = Just came back (from root word "balik" meaning to return); galing (accent on first syllable) = came from
Note: galing with accent on 2nd syllable means skill
3) Babalik ako sa Japan.
Babalik = future tense of balik
4.1) Tuwing kelan (kailan) ka nagtatrabaho dito?
Tuwing = during; ka-i-lan (formal)/kelan (informal) = when/what times; nagtatrabaho (from root word "trabaho" meaning work or to work), adding the prefix 'nag' + repeat the first syllable of "tra" (simplified to "ta") makes it present tense; dito = here
Colloquially, you can just say, "Tuwing kelan ka nag-wo-work dito?" since everyone understands the word "work". Adding 'nag' and 'wo' just makes it Filipino present progressive tense.
4.2) Gaano ka kadalas pumupunta dito?
Ga-ano/gano (informal) = how many/how much; kadalas = often; pumupunta (from root word "punta" meaning to come) = come (present tense). Punta can also mean "to go"; it all depends on what word comes next - in this case, "dito", which means here, so it means come here; if you say "punta doon", then it would mean go there.
Colloquial: Madalas ka ba dito? (You often come here?)
Note: Do NOT mispronounce 'punta' as 'puta' (which means slut). NEVER forget the 'n'... :D
Hope this helps.