New to MsC too Questions re Canada new england cruise

[latebuyer]

I’m interested in potentially going on a canada new england cruise on the meraviglia and have a few questions.

 

How do deposits work? I note bella says its one free change. Does that mean the deposit is refundable? How much is it?
What are the quality of excursions? This cruise is port intensive so i’m quite concerned the excursions are good

Are there a lot of studio cabins on this ship? It seems like there is a lot so i’m a little confused if there is or i’m misreading it

How is the food? 
How is the ship? Is entertainment good?
 

To be honest my main concern is excursions since very few sea days and i’ve wanted to go to maritimes a long time. Ports are the attractions. Not sure whether to risk going on msc.