"George has a pretty door."
Translation:عِنْد جورْج باب جَميل.
3ind George literally means "at George"
George 3ind sounds meaningless.
Prepositions in Arabic (unlike Turkish) come before the word, not after it.
This said, there might be expressions like ""George 3indahu" but this kind of poetic. In fact, I have a problem already with the word (3ind) but it is acceptable anyway.
It is similar to English somehow. There are occasions where you need to use (has) or (have) for possessive, but on other occasions you have to use (his) or (her) etc.
The expression of ( X has Y) in Arabic is, in simple terms, formed by the locative article عند (3ind: at). There is another word in fact and it is common in literature but I'm not sure why Duolingo is not using it, which is لدى (ladá). But for the time being let's stick to (3ind).
So, (X has Y) would translate into Arabic as (Y 3ind X) or (X 3ind-prefix Y), or as the above (3ind X Y). The (-prefix) here is the possessive prefix related to X; If X is singular male, it becomes (3indahu) and if it is a singular female (3indahá), and the list goes on for dual cases and plurals. It refers back to X. If we bring (X) in front of (3ind) then no need for this prefix (3inda X Y). Notice here that the original full pronunciation for (at) is (3inda) but the final "a" sometimes is dropped.
This case, of course, is quite different from the possessive. In English, George has a door is not the same as George's door or his door.
George's door or Door of George would translate as باب جورج (Bábu George).
His door would translate, simply, to بابه (bábuh).