Error When Adding Controller in ASP.NET MVC

A question when creating a controller . Because trying to create it has presented the error of the attached image.

I created 3 small classes: Dependentes , Tipobenef , TitularPlano and ProvaContext

[Table("dependentes")]
public class Dependentes
{
    public int Id { get; set; }
    [Required]
    [MaxLength(100)]
    public string Nome { get; set; }
    //public Tipobenef Tipo { get; set; }
    [Required]
    [ForeignKey("TitularesPlano")]
    public int IdTitularPlano { get; set; }
    public virtual TitularPlano Titular { get; set; }
    public virtual List<Tipobenef> Tipobenefs { get; set; }

}

public enum Tipobenef
{    
    Filho,
    Conjugue,
    Pai,
    Mae        
}

[Table("Titularesplano")]
public class TitularPlano
{
    public int Id { get; set; }
    [Required]
    [MaxLength(100)]
    public string Nome { get; set; }
    public DateTime DataNascimento { get; set; }
    [Required]
    [MaxLength(11)]
    public string CPF { get; set; }
    [Required]
    [MaxLength(8)]
    public string RG { get; set; }
}

public class ProvaContext:DbContext
{
    public ProvaContext():base("Prova")
    {

    }
    public DbSet<TitularPlano> Titulares { get; set; }
    public DbSet<Dependentes> Dependentes { get; set; }

}

Here is the part of WebConfig :

<add name="Prova"
     providerName="System.Data.SqlClient"
     connectionString="Data Source=Localhost\DESKTOP-T8VEK67; Initial Catalog=DbProva; Integrated Security=True;"/>    

I already tried all the possible names of localhost

Image 1:

Image2: