Coming is movement towards the speaker, going is moving away from the speaker. So if the words сюди (here) or туди (there) are included, that's one way to tell. Another way to distinguish them is with prefixes like при or ви, like прийшов (came), прилетів (arrived - came flying) or вийшов (left) and вилетів (departed - left flying). Otherwise you just have to rely on context to tell which direction the movement is going.
I disagree, it's not the direction of the movement, it's the time point.
No matter where I, the speaker, am standing, I can say:
1) He went home --> He departed from wherever he is with the intention to get home. At this moment he's not at home yet.
That would be, for example, Він поїхав додому / Він виїхав додому, so, по- and ви as jmango2 mentioned.
2) He came home --> He arrived to the point "home", at this moment he is there.
That would be Він приїхав додому.
For both (1) and (2) the direction of "his" movement can be away from me, but the timing of where he is when the sentence is spoken is different.
Ukrainian doesn't have to go and to come, only movement verbs like іти, (walk, go by foot), їхати (drive/ride, go by vehicle) etc, so we use these prefixes.
I'm sorry that there's no audio. For the courses that don't have text-to-speech, Duolingo hires a third party and records a limited amount of sentences. After that, if new sentences are added, there is no way for us to add any audio...
We have already been inquiring if it's possible to use some existing Ukrainian TTS to implement it. So far it's unclear how we can send this proposal, whether it's possible and how long it would take to get a response from Duo :)