declare 
MY_ROW T1%ROWTYPE;
new_id T1.id%TYPE;

TYPE TYPE_TABLE_OF_ROWS is table of T1%ROWTYPE;
TABLE_OF_ROWS TYPE_TABLE_OF_ROWS:=TYPE_TABLE_OF_ROWS(null);

begin
    select * into MY_ROW from T1 where id= 8363453 ;
    select SQ_PK_T1.NEXTVAL into new_id from dual;
    MY_ROW.id:=new_id;
--тут ещё изменения некоторых значений MY_ROW
-- например:MY_ROW.DATE_STAMP:=CURRENT_TIMESTAMP;

    TABLE_OF_ROWS( 1 ):=MY_ROW;
    DBMS_OUTPUT.put_line(TABLE_OF_ROWS( 1 ).id);

    insert into T1 select * from table(TABLE_OF_ROWS);
end;

insert into T1 row MY_ROW;

select * from ane_test_tab;

        ID        VAL
---------- ----------
          1            2 

declare
  myRow ane_test_tab%ROWTYPE;
begin
  select * into myRow from ane_test_tab where rownum= 1 ;
  myRow.id := 5 ;
  insert into ane_test_tab values myRow;
end;
/
PL/SQL procedure successfully completed

select * from ane_test_tab;

        ID        VAL
---------- ----------
          1            2 
          5            2