"I love..."
Amo la pizza.
Amo il gelato.
I'm going to assume you won't be eating anywhere where the waiter/waitress will expect fluent Italian. You wouldn't be able to learn it in time anyway.
Basically, when the waiter asks you what you want (probably in english), all you have to do is say the equivalent of "ice cream", or "pizza"
Example:
un gelato "an ice cream"
due gelati "two ice creams"
una pizza
due pizze
You may wish to add "per favore", basically "please" at the end.
But, truthfully, the waiter will probaby speak enough english that you can just order in english.
