We have started a new course. Always keep in mind that the heart of SQL is the SELECT statement.
SELECT table1.field1, table1.field2, table2.field1, table2.field2 ... FROM table1 INNER/LEFT/RIGHT JOIN table2 ON table1.common_field1 = table2.common_field1 AND table1.common_field2 = table2.common_field2
Download the notes for day 1.