CREATE TABLE consult4_basec.les (
  les_id int(11) NOT NULL AUTO_INCREMENT COMMENT 'Id',
  les_date date NOT NULL COMMENT 'Дата',
  les_time time DEFAULT NULL COMMENT 'Начало урока',
  les_status int(11) NOT NULL COMMENT 'Статус',
  PRIMARY KEY (les_id)
)
ENGINE = INNODB,
CHARACTER SET utf8,
COLLATE utf8_general_ci,
COMMENT = 'Уроки';

INSERT INTO les(les_id, les_date, les_time, les_status) VALUES
(1, '2021-01-11', NULL, 0),
(2, '2021-01-15', NULL, 0),
(3, '2021-01-22', NULL, 0),
(4, '2021-01-25', NULL, 0),
(5, '2021-01-27', NULL, 0),
(6, '2021-01-29', NULL, 0),
(7, '2021-02-01', NULL, 0),
(8, '2021-02-05', NULL, 0);

SELECT les_id, les_date
FROM les ORDER BY les_date DESC;

SELECT *
FROM les
WHERE les_date >= @today
ORDER BY les_date LIMIT 2;

SELECT *
FROM les 
WHERE les_date < date(NOW());

SELECT *
FROM les
WHERE les_date >= date(now())
ORDER BY les_date LIMIT 2
  UNION ALL
SELECT *
FROM les 
WHERE les_date < date(NOW());

Incorrect usage of UNION and ORDER BY