The "Freeway" is an oddity in American English, it is a word mostly (only?) used in California and refers to the large multi-lane highways they have in that state.  Freeways have no traffic lights and are supposed to be high speed, but California traffic jams are world renowned.

California is also the only state i know if where they refer to their highways with a number preceded by the definite article "the".  Californians talk about taking "the Five" or "the 101" etc where in most of the rest of the country we would say Route 5 or Highway 101.

Anyway the directions above want you to get on the nearest freeway and get off the freeway at the Seventh Avenue exit.  Exits are how you get off the freeway and get on to local roads.  The exits are usually well marked with signs telling you the road or other freeway you will be getting on to if you exit there.

Now all you need is a good map :-)