EntityFramework包没有安装在项目上

I am having trouble getting the EF to install on my very simple project called 'Match' (just now learning MVC, better late than never). The general context here is that I created the Model class with only 2 fields and now I want to change the Model class to have a few more fields/properties. I have made the change in the Model class and am now trying to update the DB to match. I am trying to use Update-Database from EF to do that.I am having trouble getting the EF to install o