A statement is a sentence that tells you something. A question is a sentence that asks you something. A statement does not require an answer. A question requires an answer.

statement: I like EnglishClub.  
question: Do you like EnglishClub? Yes
Why do you like EnglishClub? Because...

A written question in English always ends with a question mark:

In this lesson we look at basic question structure and question types, followed by a quiz to check your understanding:

Question structure

Question types

Questions quiz

Questions are also known as "interrogatives".