There is a diference between the SQL term "join" and "relationships".
The link Wiedmann provided gives you the syntax of a guery that includes a join statement - the answer to what seemed to be your question
how to jion between tables
You can also create relationships between tables. Relationships define how data in one table is related to data in another table. The join statement joins the data from different tables (according to the join specified in the query) into a single recordset.
The fact that you seem to use join and relationship interchangeable means that it is not longer clear what you are actually looking for.