ヘルプを読むと分かるよ

uses
Clipbrd;

procedure TForm1.Button1Click(Sender: TObject);
var
bmp:TBitmap;
begin
bmp := TBitmap.Create;
try
bmp.LoadFromFile('C:\Test.bmp');
Clipboard.Assign(bmp);
finally
bmp.Free;
end;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
if Clipboard.HasFormat(CF_BITMAP) then Image1.Picture.Bitmap.Assign(Clipboard);
end;