Inserting collums data from 3 different tables into new table

Question

I have 3 table,

 

table: "db.Users"

has columns: UserId, FirstName, Lastname, Email

 

table: "db.Roles"

has columns:  RolesId, RoleName 

 

Table: "db.UserRoles" 

Has columns:  UserId, RolesId

 

And I would like to Insert the information from the top

3 tables into a new existing table named

Table: "db.UsersWithRoles" 

 

with  5 columns:  UserId, FirstName, Lastname, Email, RoleName

 

 

I have tried to use  Inner join but it is not really what i was looking for 

because i want to add it to an existing table so i can read it with C# mvc and post it on my website

I am not really sure how I am able to achive this.