Error displaying message in PL-SQL

Code

DECLARE
BEGIN

    FOR I IN (SELECT * FROM PRODUTOS_TESTE2) LOOP
          DBMS_OUTPUT.PUT_LINE(I.codigo|| ' - ' || I.categoria || ' - ' || I.VALOR); 
    END LOOP; 
END;

Error message:

Relatório de erros -
ORA-06550: line 5, column 28:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 5, column 14:
PL/SQL: SQL Statement ignored
ORA-06550: line 6, column 32:
PLS-00364: loop index variable 'I' use is invalid
ORA-06550: line 6, column 11:
PL/SQL: Statement ignored
06550. 00000 -  "line %s, column %s:\n%s"
*Cause:    Usually a PL/SQL compilation error.
*Action:

Table Structure