Trip Insurance isn't as clearcut as you might think, in fact it's quite opaque. This site has a lot of helpful information so you don't make an expensive mistake. Click around, there's much here.
https://tripinsurancestore.com/
If you've already made travel plans you can enter the information and get side by side price and feature comparisons of 9 insurance companies.
Here's another place with answers to important questions.
The TripInsuranceStore.com Blog - "If You Are Dead Serious About Understanding How Cruise, Travel & Trip Insurance Works, This Will Be The Most Important Blog You Have Ever Read"