You can do anything you want. As long as the puntcuation is correct. That's pretty much the only rule with the English language.
Yes, a sentence can start with a pronoun. For example, "She went to the store."
the answer to that question is "who is the owner of this car?"
yes you can like for example, Was it you who stole the money?
yes specially if the sentence is an interrogative sentence. for example "From where does this package came from".
Yes. for example With referance to the request by......................
yes for example: HE/SHE went to the supermarket
An example is this one, so yes you can!
Yes, you can start a sentence with "although." For example: "Although it was raining, we decided to go for a walk."
Yes: For Example; Which of the items in the box belong to you?; This is an interrogative sentence.
Yes. 'Who took my sandwich?' is a great example of a sentence in the form of a question.
An example of a sentence beginning with our: Our grandmother died in prison.
No, why should it be? Well if it's at the start of a sentence, but really, how many sentences start with the word example?