To call a sub procedure, just use the sub procedure name as a statement. Here is another example of calling a sub procedure:

SQL> CREATE OR REPLACE PROCEDURE WELCOME AS

2 PROCEDURE WELCOME_PRINT(S CHAR) AS

3 BEGIN

4 DBMS_OUTPUT.PUT_LINE('Welcome to ' || S);

5 END;

6 BEGIN

7 WELCOME_PRINT('globalguideline');

8 END;

9 /

SQL> EXECUTE WELCOME;

Welcome to globalguideline