First, make sure you have a relationship between the two tables that will work:
Customers::__pk_CustomerID = Jobs::_fk_CustomerID
__pk_CustomerID is an auto-entered serial number field so that each customer gets a unique number that identifies their record.
In your jobs table, you'll need to decide whether or not you really need the customer name, address and phone 3 fields. There are two approaches here you can use and both show the selected contact info for a customer, but the way the contact data is managed differs and which is best depends on how run your business.
See this thread that describes both a "dynamic" link where any edits to the Customers table automatically updates all contact info shown on your jobs layouts and also a "look up" method that copies the information over to capture a "snapshot" of the contact info that was current at the time the customer was selected for your job record.
This thread illustrates a very simple way to set this up. While that makes it easy to set up, it isn't always the best approach for managing large value lists that might list 100's of customers. If that's what you need, still set it up like the above link describes, but then let me know and I'll share some methods for trimming large value lists down to a more manageable size.