Marking the object with を
What you eat, drink, read, or ask for: を marks the object of the action.
Coco-sensei

Learn
English relies heavily on word order: in “I eat sushi,” sushi follows the verb. Japanese puts を after the object, with the verb later: 寿司 を 食べる. The particle marks sushi as what is eaten. Learn the noun and its particle together.
Pronunciation
The particle を has its own character but is normally pronounced o, like お. In modern standard Japanese, its main use is this grammatical particle.
You can already make a useful request with noun + を + ください. 寿司 を ください means “Sushi, please,” or “Please give me sushi.” Here ください expresses the request; を still marks what you are asking for.
Examples
寿司 を ください。
Sushi, please.
パン を 食べる。
I eat bread.
本 を 読む。
I read a book.