one thing I find really difficult to learn is to change the way we think. You can become super fast in doing live translation from Ukrainian to English, but in the end, if you are using unknown to native speakers idioms or language constructions, they won't understand you no matter how complex your vocabulary is. Unfortunately, it is not 1 to 1 translation, and I actually find watching livestreams and listening to podcasts really useful because of that.
for example:
original: роби ось так
direct translation is: do here as
better translation: do the same
another better translation: make like so
#2 original: I call it a day
direct: Я кличу це днем
better translation: Ось і весь день
accurate translation: На сьогодні все (закінчив)