Unfortunately I can't show dictionary I use usually because it's Esperanto-Russian and Russian-Esperanto but here's Google Translate screen with translating "bone" as "good". Generally I used to think that "well" and "good" are synonims, isn't it?
When you move mouse over some word in a sentence on Duolingo you can see translations of words. I don't recommend using only Google Translate because translations can be bad. Generally, "Bona" is an adjective and usually describes nouns and pronouns. "Bone" is an adverb and modifies verbs, adverbs and adjectives.