I concur with Billy Dat's recommendations, including a visit to the Doge's Palace, and in particular would agree that the best way to experience and absorb the spirit of Venice is to immerse yourself in its timeless character by spending at least half of your time wandering aimlessly away from the heavily trafficked areas. Just be sure to download the Google Map of the island to your phone before you set out so that you can use GPS to locate your position, track the direction of your movement, and thereby find your way back to a familiar place at any time even when offline. One more suggestion: Make a reservation (or, to improve your chances of securing a table, ask your hotel concierge to make a reservation) for a dinner at Osteria l'Orto dei Mori [
https://www.osteriaortodeimori.com/i-nostri-piatti/]. It's a small place, off the beaten path, where you'll join a pleasant mix of locals and some lucky tourists enjoying splendid food and wines at relatively modest prices.