declare @t table (id int, date datetime);

insert into @t values 
(6	,'2020-11-06 08:30:00.000'),
(6	,'2020-11-06 10:05:03.857'),
(6	,'2020-11-06 10:05:07.107'),
(6	,'2020-11-06 10:07:27.967'),
(10	,'2020-11-06 10:14:11.233'),
(10	,'2020-11-06 11:05:00.000'),
(9	,'2020-11-06 12:14:00.000'),
(9	,'2020-11-06 12:35:00.000'),
(9	,'2020-11-06 13:30:00.000'),
(6	,'2020-11-06 15:00:00.000'),
(6	,'2020-11-06 17:29:27.520');

with x as (
    select row_number() over (order by 1/0) as [rn], * from @t
),
y as (
    select row_number() over (order by [rn]) - row_number() over (partition by [id] order by [rn]) as rn2, * from x
)
select
      [id],
      min([date]) as [min_date],
      max([date]) as [max_date]
from y
group by [rn2], [id]