Enter Manage | Database | Tables and create tables.
Enter Manage | Database | Fields and define fields for them.
Use the Relationships tab to link them in relationships. (It's a bit like the relationships tool in Access.)
Unlike Access, all your relationships have to be defined in the relationships tab.
Forget about SQL, you don't use it with Filemaker like you might with Access.
Portals in Filemaker are like subforms and subreports in Access.
Learn how to perform finds--a found set is a bit like a record set in Access. Unlike access, you can design and run these directly against a layout instead of using a query manager.
You might investigate some of the Free Templates available.
White Paper for FMP Novices
Starting Point Template
There are other Filemaker forums