How to capture an ID row with AUTO_INCREMENT property

Question

I have created a request table with different fields including and id field.

Now the problem I'm facing is I want to query this database and select the id of a particular data entry (request) I know I can use 'WHERE' clause but most the entries might have similar data so I will get more than 1 id and probably one request

Here is the code for inserting the records :

     $sql = "INSERT INTO requests (user_from,user_from_id,user_to) VALUES (:myname,:user2id,:user2)";
     $stmt = $pdo->prepare($sql);
     //Bind the variables.
     $stmt->bindValue(':myname', $myname);
     $stmt->bindValue(':user2id', $user2id);
     $stmt->bindValue(':user2', $user2);




   //Execute the statement .
     $result = $stmt->execute();

But I don't know how to query the database for the newly generated id.