Positions of Prepositions

What are you talking ABOUT?
What are you thinking ABOUT?
What country was he born FROM? (IN)
Who do you wish to speak TO?
What are they going to use the money FOR?
Which restaurant do you want to eat FOR? (AT)
Which shop did she buy the dress TO? (FROM)
Which hotel did he go TO?
Which magazine do you want to look AT?
Which room do you have your lesson TO? (IN)
Where did all that dirt come FROM?
What are you smiling AT?

Obs.: Embora essas preposições estejam no fim das perguntas, elas podem iniciá-las. Vemos as preposições antes dos pronomes interrogativos em contextos formais ou científicos. No dia a dia, os falantes nativos preferem usá-las no fim das perguntas.

What are you thinking FOR?
What country was he born IN?
Which restaurant do you want to eat AT?
Which shop did you buy the dress AT?
Who was the book written FOR?
Which hotel did you go TO?
Who did they sell their house FOR?
What is the guide poiting TO?
Where did all that dirt come FROM?
What are you smiling AT?

Está correto?

In questions with Wh- words at the beginning a preposition comes at the end. Wh-words being Where/What/Which, etc.

It's also worth that it happens when the verb (of the likely answer will take a preposition) I am thinking for applying after my high school to a us univeirsity
What are you thinking FOR?

I was born in Brazil.
What country was he born IN?

I bought my dress AT Tacaruna Mall (AT a store in the Tacaruna Mall), "Tacaruna Shopping") in Portuguese. I bought my dress AT Manaira Mall or AT Riomar Recife Mall: can't remember where I bought it.
Which shop did you buy the dress AT?

That diirt come up from my shoes. It travelled all way attached to the shoes and at the very instant I entered home it (the dirt) came off!
Where did all that dirt come FROM?