How to dbms_output record variable

set serveroutput on;
DECLARE
  PI_STARTDATE DATE;
  PO_STATUS NUMBER;
  PO_HEADER VARCHAR2(200);
  PO_LABEL VARCHAR2(200);
  PO_RECORD SYS_REFCURSOR;
  PO_NEXTINCSTARTDATE DATE;
BEGIN
  PI_STARTDATE := to_date('2020-05-01','yyyy-MM-dd');
  PCK_FAB_REPORTS.PRC_MONTHLY_WRTOFF_REPORT(
    PI_STARTDATE => PI_STARTDATE,
    PO_STATUS => PO_STATUS,
    PO_HEADER => PO_HEADER,
    PO_LABEL => PO_LABEL,
    PO_RECORD => PO_RECORD,
    PO_NEXTINCSTARTDATE => PO_NEXTINCSTARTDATE);
DBMS_OUTPUT.PUT_LINE('PO_STATUS = ' || PO_STATUS);
DBMS_OUTPUT.PUT_LINE('PO_HEADER = ' || PO_HEADER);
DBMS_OUTPUT.PUT_LINE('PO_LABEL = ' || PO_LABEL);
DBMS_OUTPUT.PUT_LINE('PO_NEXTINCSTARTDATE = ' || PO_NEXTINCSTARTDATE);
END;

I want to unit test the procedure and want to display the ref cursor variable as well. How to display ref cursor using dbms?

Here's an example based on Scott's EMP table:

SQL> set serveroutput on
SQL>
SQL> declare
  2    l_ename   emp.ename%type;
  3    l_job     emp.job%type;
  4    l_rc      sys_refcursor;
  5  begin
  6    open l_rc for select ename, job from emp
  7                  where deptno = 10;
  8
  9    loop
 10      fetch l_rc into l_ename, l_job;
 11      exit when l_rc%notfound;
 12
 13      dbms_output.put_line(l_ename ||' '|| l_job);
 14    end loop;
 15    close l_rc;
 16  end;
 17  /
CLARK MANAGER
KING PRESIDENT
MILLER CLERK

PL/SQL procedure successfully completed.

SQL>

So: you have to fetch refcursor into variables and then display contents of those variables.