Toad for Oracle..How to execute multiple statements?

F9 executes only one statement. By default Toad will try to execute the statement wherever your cursor is or treat all the highlighted text as a statement and try to execute that. A ; is not necessary in this case.

F5 is "Execute as Script" which means that Toad will take either the complete highlighted text (or everything in your editor if nothing is highlighted) containing more than one statement and execute it like it was a script in SQL*Plus. So, in this case every statement must be followed by a ; and sometimes (in PL/SQL cases) ended with a /.

Highlight everything you want to run and run as a script. You can do that by clicking the icon on the menu bar that looks like a text file with a lightning bolt on it. That is the same as hitting F5. So if F5 doesn't work you probably have an error in your script.

Do you have semicolons after each statement?

Wrap the multiple statements in a BEGIN END block to make them one statement and add a slash after the END; clause.

BEGIN
  insert into books
  (id, title, author)
  values
  (books_seq.nextval, 'The Bite in the Apple', 'Chrisann Brennan');

  insert into books
  (id, title, author)
  values
  (books_seq.nextval, 'The Restaurant at the End of the Universe', 'Douglas Adams');
END;
/

That way, it is just ctrl-a then ctrl-enter and it goes.