One-to-one relashionship Entity Framework and .NET

I am creating a relationship between my classes using code first. The integration happens with MySql, however, after migrating it consider the relationship as one-to-many when I check my workbench ERD.

How can I make a relashionship one-to-one using the classes mentioned below?

Here is my code:

public class About  
{
    [ForeignKey("User")]
    public int Userid { get; set; }
    public int id { get; set; }
    public string about_file { get; set; }
    public string about_desc { get; set; }
    public virtual User User { get; set; }
}

public class User 
{
    [Key]
    public int id { get; set; }
    public string login { get; set; }
    public string password { get; set; }
    public virtual About About { get; set; }
    public ICollection<Offers> Offers { get; set; } = new List<Offers>();
    public ICollection<Portfolio> Portifolios { get; set; } = new List<Portfolio>();
}

Microsoft.EntityFrameworkCore Version: {5.0.7}