Oracle 18c

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CREATE TABLE invoicetable (
  invoicenum    NUMBER(10,0),
  invoiceamount NUMBER(17,2),
  invoicedate   DATE
);
CREATE PROCEDURE InvoiceDetails (
  p_FromDate   IN InvoiceTable.InvoiceDate%TYPE, -- Use the types from the table
  p_ToDate     IN InvoiceTable.InvoiceDate%TYPE,
  p_InvoiceNum IN InvoiceTable.InvoiceNum%TYPE
)
IS 
  inv_info invoicetable%ROWTYPE;
BEGIN
  SELECT * 
  INTO   INV_info
  FROM   invoicetable
  WHERE  InvoiceNum = p_InvoiceNum -- Don't have the same variable name as the
                                   -- column name. One prectice is to prefix the
                                   -- parameter names with p_ to distinguish
                                   -- that they were passed from outside the
                                   -- procedure.
  AND    InvoiceDate BETWEEN p_FromDate AND p_ToDate;

  dbms_output.put_line('ID:     ' || INV_info.InvoiceNum);
  dbms_output.put_line('Amount: ' || INV_info.InvoiceAmount);
  dbms_output.put_line('Date:   ' || TO_CHAR( INV_info.InvoiceDate, 'YYYY-MM-DD' ) );
EXCEPTION
  WHEN NO_DATA_FOUND THEN -- Handle the exception when no rows are found.
    dbms_output.put_line('No Invoices exist.');
  WHEN TOO_MANY_ROWS THEN -- Handle the exception when multiple rows are found.
    dbms_output.put_line('Multiple invices exist.');
END InvoiceDetails;
/
BEGIN
  dbms_output.put_line(' '); -- You don't need this line.
  Invoicedetails( DATE '2020-01-01',DATE '2020-01-05',200651);
END;
/
1 rows affected

dbms_output:
 
No Invoices exist.

INSERT INTO  invoicetable (invoicenum, invoiceamount, invoicedate )
VALUES ( 200651, 200, DATE '2020-01-04' );
1 rows affected

BEGIN
  dbms_output.put_line(' '); -- You don't need this line.
  Invoicedetails( DATE '2020-01-01',DATE '2020-01-05',200651);
END;
/
1 rows affected

dbms_output:
 
ID:     200651
Amount: 200
Date:   2020-01-04

INSERT INTO  invoicetable (invoicenum, invoiceamount, invoicedate )
VALUES ( 200651, 300, DATE '2020-01-05' );
1 rows affected

BEGIN
  dbms_output.put_line(' '); -- You don't need this line.
  Invoicedetails( DATE '2020-01-01',DATE '2020-01-05',200651);
END;
/
1 rows affected

dbms_output:
 
Multiple invices exist.