"I eat an orange."
Translation:Ich esse eine Orange.
I'm also a native Spanish-speaker, and actually I feel I'm learning a lot more when using English to learn another language, since I can understand faster because I have another reference, not just my native language. I also started Italian and at school we have French class, so when something is difficult to understand in one language I compare it to the others and most of the time one of them will enable me to understand faster than if I just compared it to one.
Well, that's my situation.
As with learning any language, daily studying will help. Go through the lessons and just get to know the words without trying to memorize all the rules first. Re-do the lessons a few times until the words flow smoothly. Then go back and look at the "rules". It'll be easier to learn if you're not stressing over the rules and just read the lessons first.
No. German articles depend only on the case and the gender of the noun. It is irrelevant if the noun starts with a vocal or not. In this example the case is akkusativ and the noun is feminine, hence it must be eine. If the noun would have been masculin (e.g. Apfel) it would have been einen. Long story short: Every indefinite article in German translates to a/an/one in English.
Verbs are second. Subject does not have to be first! See more here: http://german.about.com/library/weekly/aa032700a.htm
There are always exceptions, but I've read that words with these endings tend to be a certain gender - masculine: -er, -el, -en, -ling, -ig, -ich; feminine: -e, -in, -ung, -in with female roles (e.g. freund - freundin), -schaft, -ei, -tät, -heit, -keit, -ie, tion; neuter: -chen, -lein, -um, -ium, Ge-
-ig and -ich are standard endings for adjectives so they don't have a gender. Another thing to keep in mind is that these rules only apply if the ending has its own syllable, i.e. the noun has at least 2 syllables. E.g.:
der Dung is masculine although it ends with -ung, but here -ung is not an ending but part of the word itself. There should be only very few of these, just be aware that they exist.