How to Specify Entity Framework Core Table Mapping?

I've made a simple Entity Framework ASP Core Application which works but I do not know why:

I've made a context like this:

public class AstootContext : DbContext
{
    public AstootContext(DbContextOptions<AstootContext> options)
        : base(options)
    { }

    public DbSet<Account> Accounts { get; set; }
    public DbSet<User> Users { get; set; }
}

And I have two tables with models like this:

public class Account
{
    public int Id { get; set; }
    public string Username { get; set; }
    public string PasswordHash { get; set; }
    public DateTime Created { get; set; }

    List<User> Users { get; set; }
}

public class User
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
    public DateTime Birthday { get; set; }
    public Account Account { get; set; }
}

The interesting thing is that when I run my application it actually can pick up the data. It just seems weird because I have not specified any table mapping. I'm assuming this just automaps because the specified tables are the same name.

My questions are:

1. How do I specify Table explicit table mapping in case I do not want my model names to be exactly the same as the DB?

2. How do I specify Custom Column Mapping.

3. Is there anything special I have to specify for Primary/Foreign Keys

edit

To clarify

1. say I had a table in the DB MyAccounts and I wanted to map that to a entity Accounts.

2. Say I had a column password and I wanted that to map to a POCO property PasswordHash