How to handle related database tables

I am trying to build an application where my customer can add a client and a primary contact to a custom set of data tables I have created.

  1. I need to be able to add the Client to the Client table, get the ID Key then…

  2. Add the Contact to the Contact table and assign it the association the Client table with the Client ID key.

  3. I also have a table that defines the types of Clients. In my form this is a drop down select. How can I have the selected item enter it’s related ID key in the Client table?

I have not found anyway to do this. Does this system support many to one relationships, and order of operations for form submissions?