I would like to say ''the eagle flies high in the sky -
aquila in caelo altum volat''is that correct? i'm not sure how to write the word''high''in this context,should it be the neuter or feminine accusative adjective.
the sentence "The eagle flies high in the sky “ can be translated correctly as follows:
-“Alte volat aquila in caelo” where the positive adverb “alte” corresponds to “high”.
-“Altissime volat aquila in caelo” where the superlative adverb “altissime” corresponds to “high”, as we read in Suetonius, Life of Augustus, chapter 94, section 7.
As for “altum” in your translation, such a neuter is wrong as well as it would be wrong to use “alta” in the nominative feminine as an adjective agreed with “aquila”.
In short, the English expression “high” in “The eagle flies high in the sky” can be translated as “alte” (positive adverb), “altissime” (superlative adverb) and “in altum”(adverbial expression) which however is not suitable here, because “In altum volat aquila in caelo” would sound not so good in Latin where “IN altum” and “IN caelo” would be a bad repetition.
Lastly, I have to point out that both “Alte volat aquila in caelo” and “Altissime volat aquila in caelo” have the best Latin word order, where case inflection indicates the role of a word in a sentence.