type TClass1 = class
  procedure Do4All;
  procedure Method1; abstract;
  procedure Method2; abstract;
end;

type TClass2 = class (Tclass1)
  procedure Method1 override;
  procedure Method2 override;
end;
{$R *.dfm}

type TClass1 = class
  procedure Do4All;
  procedure Method1; abstract; virtual;
  procedure Method2; abstract; virtual;
end;

type TClass2 = class (Tclass1)
  procedure Method1 override;
  procedure Method2 override;
end;
{$R *.dfm}

type TClass1 = class
  procedure Do4All;
  procedure Method1; virtual; abstract;
  procedure Method2; virtual; abstract;
end;

type TClass2 = class (Tclass1)
  procedure Method1 override;
  procedure Method2 override;
end;
{$R *.dfm}

unit wol;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type TClass1 = class
  procedure Do4All;
  procedure Method1; virtual; abstract;
  procedure Method2; virtual; abstract;
end;

type TClass2 = class (Tclass1)
  procedure Method1; override;
  procedure Method2; override;
end;
{$R *.dfm}

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

 procedure tClass1.Do4All;
 begin
   Method1;
   Method2;
 end;

 procedure tClass2.Method1;
 begin
   ShowMessage ('Method1');
 end;

procedure tClass2.Method2;
 begin
   ShowMessage ('Method2');
 end;

procedure TForm1.Button1Click(Sender: TObject);
var cl2 : TClass2;
begin
  try
    cl2 := TClass2.Create;
    cl2.Do4All;
  finally
    FreeAndNil (cl2)
  end;

end;

end.