SQL Server 2019

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE t
( DateTime datetime NOT NULL
, MonitorId INT NOT NULL
, Value decimal(10,2) NOT NULL
, Status Int NOT NULL
) ;

INSERT INTO t VALUES ('2022-11-21 00:00:05', 1, 5, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:01:05', 1, 10, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:02:05', 1, 15, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:03:05', 1, 20, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:04:05', 1, 30, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:05:05', 1, 123, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:06:05', 1, 456, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:07:05', 1, 789, 10) ;

INSERT INTO t VALUES ('2022-11-21 00:00:05', 2, 5, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:01:05', 2, 10, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:02:05', 2, 15, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:03:05', 2, 20, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:04:05', 2, 30, 1) ;
INSERT INTO t VALUES ('2022-11-21 00:05:05', 2, 123, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:06:05', 2, 456, 10) ;
INSERT INTO t VALUES ('2022-11-21 00:07:05', 2, 789, 10) ;

Select *
,(
  select top 1 Value
  from t b
  where b.Status = 10
  and a.MonitorId = b.MonitorId
  and a.DateTime > b.DateTime
  order by b.DateTime desc
) LAGValue
From t a
order by a.MonitorId
,a.DateTime

DateTime	MonitorId	Value	Status	LAGValue
2022-11-21 00:00:05.000	1	5.00	10	null
2022-11-21 00:01:05.000	1	10.00	10	5.00
2022-11-21 00:02:05.000	1	15.00	1	10.00
2022-11-21 00:03:05.000	1	20.00	1	10.00
2022-11-21 00:04:05.000	1	30.00	1	10.00
2022-11-21 00:05:05.000	1	123.00	10	10.00
2022-11-21 00:06:05.000	1	456.00	10	123.00
2022-11-21 00:07:05.000	1	789.00	10	456.00
2022-11-21 00:00:05.000	2	5.00	10	null
2022-11-21 00:01:05.000	2	10.00	10	5.00
2022-11-21 00:02:05.000	2	15.00	1	10.00
2022-11-21 00:03:05.000	2	20.00	1	10.00
2022-11-21 00:04:05.000	2	30.00	1	10.00
2022-11-21 00:05:05.000	2	123.00	10	10.00
2022-11-21 00:06:05.000	2	456.00	10	123.00
2022-11-21 00:07:05.000	2	789.00	10	456.00