Hello, I am 16 and my girlfriend just got strep throat, I don't necessarily have it yet but what are some things I can do to prevent/help the chances?

No sharing. Spread by sharing , kissing , drinking after each others , etc.
STREP TONSILLITIS. Avoid kissing your girlfriend due to the infection. Wash your hands frequently to avoid contamination. She will not be infectious after a day of antibiotics but to finish it for complete cure.