Data is added to a table with INSERT INTO.

INSERT INTO `<table_name>` (`<column_1>`, `<column_2>`)
VALUES ("<data_1>", "<data_2>"), ("<data_1>", "<data_2>"),("<data_1>", "<data_2>"), ("<data_1>", "<data_2>"),("<data_1>", "<data_2>"), ("<data_1>", "<data_2>");

Add Column

ALTER TABLE employees ADD email VARCHAR(255);

Add Entry

UPDATE employees SET email = "bob@gmail.com" WHERE emp_no = 1000;