Oracle Run Procedure with one in parameter and multiple out parameter

I just started working with Oracle and I'm using SQL Developer to test before I start adding stuff to my application, but I'm running into issues because Oracle behaves differently than every other database engine I've worked with.

I created a dummy table:

CREATE TABLE "ROOT"."EMPLOYEES" 
(   "ID" NUMBER NOT NULL ENABLE, 
"FIRSTNAME" VARCHAR2(30 BYTE) NOT NULL ENABLE, 
"LASTNAME" VARCHAR2(30 BYTE) NOT NULL ENABLE, 
"EMAIL" VARCHAR2(40 BYTE) NOT NULL ENABLE, 
 CONSTRAINT "EMPLOYEES_PK" PRIMARY KEY ("ID")
)

And Then I created a Procedure:

 create or replace PROCEDURE get_employee
(
  emp_id IN NUMBER,
  m_FirstName OUT Varchar2,
  m_LastName OUT Varchar2,
  m_Email OUT Varchar2
)
AS
BEGIN
SELECT 
   FirstName
   ,LastName
   ,Email
INTO
   m_FirstName,
   m_LastName,
   m_Email
FROM EMPLOYEES
WHERE
  ID = emp_id;
END get_employee;

The problem is I get compilation errors when I try to run the procedure:

Declare x VARCHAR2(30);
y VARCHAR2(30);
z VARCHAR2(40);

Begin
exec GET_EMPLOYEE(1, :x, :y, :z);
SYS.DBMS_OUTPUT.PUT_LINE(x);
End; 

I get this error:

ORA-06550: line 8, column 4:
PLS-00103: Encountered the symbol "end-of-file" when expecting one of the following:

( begin case declare end exception exit for goto if loop mod
null pragma raise return select update while with
an identifier a double-quoted
06550. 00000 – "line %s, column %s:\n%s"
*Cause: Usually a PL/SQL compilation error.
*Action:
PL/SQL procedure successfully completed.

I'm really not sure how to change my call to the procedure to make it work with SQL Developer. Any help would be greatly appreciated.