DDL = Data Definition Language. It includes CREATE, ALTER and DROP statements.
DML = Data Manipulation Language. It includes DELETE, INSERT, SELECT, UPDATE and MERGE statements.
CREATE TABLE MyTable(FirstColumn int not null primary key, SecondColumn varchar(100)); --< This is Table DDL
INSERT INTO MyTable
VALUES ( 1, 'One'), ( 2, 'Two' );
In SQL Management Studio if you right click a table and select script as create>new query window, it will script the table DDL. Then you can write the insert(s) with sample data.