If all the same chords are used in all styles of song, then how do I make a song sound classical, bluesy or like rock and roll???

Listen and emulate.

Pick out some classical, blues, and rock recordings. Find out what chords are being played. Check out the syncopation (straight 8ths, swing, etc). Learn the songs and find out what makes them tick from the inside out. Once you can physically play the song, analyze it.

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"You must stab him in the heart with the Bone Saber of Zumacalis... well, you could stab him in the head or the lungs, too... and the saber, it probably doesn't have to be bone, just anything sharp lying around the house... you could poke him with a pillow and kill him."

- Aqua Teen Hunger Force, The Universal Re-Monster

Thanks!!!