Concept of using だ and sentence structure


I'm fairly new to learning japanese but I have the basic grammar down. The
main thing that's confusing is the sentence structure. For instance, I sent
this message to my friend who is native to Japan for him to check over it
`あなたはたべるすし？` I attempted to say "do you eat sushi?" In my mind this worked
perfectly, anata=you, taberu=eat, sushi=sushi. So he responds with this `No,
it's "あなたはすしたべる?"`

This leads me to wonder if there are any specific rules on where in the
sentence the subject, verb, direction, direct object, etc have to come. I am
currently learning japanese in addition to full time school work including
Spanish classes. The only resources I have are the internet and my friends.

Please explain in simpleton terms, if you need any extra clarity please notify
me. It's late and I'm typing this on my mobile device. Thank you very much

Part 2(I didn't want to make another question for this simple question):

If you were to say you like someone, would

`わたしはあなたがすき` Be correct? I don't fully understand when to use the particle だ.
My gut is telling me that I should put だ after suki, but I don't know why




だ is the dictionary/casual form of です, which in your sentence expresses a
state of affairs (e.g. you liking the other).

As for the sentence order, between

> あなたはすし（を）たべる? Do you eat sushi?

and

> あなたはたべるすし？ Are you an eating sushi?

the former contains a particle (を) left out in your friend's response that
points out an object of your action (e.g. すしをたべる eat what? sushi), while the
latter's word order shows a compounded noun (e.g. たべるすし eating sushi, or sushi
that eats, which doesn't make sense).




だ is the dictionary/casual form of です, which in your sentence expresses a
state of affairs (e.g. you liking the other).

As for the sentence order, between

> あなたはすし（を）たべる? Do you eat sushi?

and

> あなたはたべるすし？ Are you an eating sushi?

the former contains a particle (を) left out in your friend's response that
points out an object of your action (e.g. すしをたべる eat what? sushi), while the
latter's word order shows a compounded noun (e.g. たべるすし eating sushi, or sushi
that eats, which doesn't make sense).

