Hi. I'm here to echo what everyone else said: this is too much. Here's what your trip will actually look like:
DAY 1 - Arrived in Rome. Be super jet lagged and exhausted. Sleep, have dinner, sleep some more.
DAY 2 - Rome
DAY 3 - Rome & Vatican
DAY 4 - Wake up. Travel to train station. Wait for train. Train to Naples. Arrive in Naples around noon-ish. Afternoon and evening in Naples.
DAY 5 - Wake up. Travel to train station. Wait for train. Train to Pompeii. Pompeii. Back to train. Train to Florence. Arrive Florence late. Sleep.
DAY 6 - Florence
DAY 7 - Tuscany (assuming this is a day tour from Florence?)
DAY 8 - Wake up. Travel to train station. Wait for train. Train to Pisa. Look at tower. Back to train station. Train to La Spezia. Train to Varnazza. Sleep.
DAY 9 - Cinque Terre
DAY 10 - Wake up. Travel to train station. Wait for train. Train to Varenna (assuming a train change here too) Lake Como for like a minute.
DAY 11 - Wake up. Travel to train station. Wait for train. Train to Venice. Evening in Venice.
DAY 12 - Venice
DAY 13 - Wake up. Travel to train station. Wait for train. Train to Milan. Evening in Milan.
DAY 14 - Fly back in the morning
In 14 days, you have exactly five days without travel. And one of those will be spent at the Vatican, which is an exhausting day.
So yeah. You'll need to cut something here.
Please note that I say this with love and kindness, just as ALL the people did on these very same boards when I planned my first disastrous trip to Europe ten years ago. We planned WAY too much even just within Paris and London--like too much per day. We wanted to SEE ALL THE THINGS. And I had the most miserable time. It's a miracle I've since returned to Europe (several times) but I learned from that first ill-fated trip. Slow down and assume you will return. And even if you don't ever return (because tomorrow is not a promise) at least you will have ENJOYED a slice of Italy rather than force-feeding yourself ALL of Italy.