How to update 3 table data by using entity framwork

Question

Here i am able to add 3 table data in sql server

 

//This code is for adding data in table 

 

userData.Franchises.Add(franchiseData);

foreach (var item in userData.Franchises)

{

item.Fees.Add(feeData);

}

db.Users.Add(userData);

db.SaveChanges();

 

but I want to know how to update these able by using entity framework