"Ghassan is a very hungry Lebanese engineer."
Translation:غَسّان مُهَنْدِس لُبْنانِيّ جَوْعان جِدّاً.
Start with the beginning of the sentence. The name "Ghassan". "Is" does not get translated in Arabic in the present tense. Then we have a list of adjectives telling what kind of engineer Ghassan is. Adjectives come after the word they are describing. So the word "engineer" has to come next. When adjectives are in a list, they are translated in reverse order. (Tip for later: If the adjectives are around the word "and," keep them in order around the word "and")
If i understand your question correctly, you are wondering why the word order changed between the English and the Arabic? It seems that Arabic is like many other languages with respect to nouns and adjectives: the noun (engineer) comes first, then the modifying adjectives (Lebanese and hungry). I read one comment that said adjectives can sometimes go first, but typically they must come after the noun.