MySQL 8.0

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Records: 7  Duplicates: 0  Warnings: 0

select act_id,
       max(case when new_col='min_value' then amount     end) as ini_amt,
       max(case when new_col='min_value' then created_dt end) as ini_dt,
       max(case when new_col='min_value' then created_by end) as ini_usr,
       max(case when new_col='max_value' then amount     end) as fnl_amt,
       max(case when new_col='max_value' then created_dt end) as fnl_dt,
       max(case when new_col='max_value' then created_by end) as fnl_usr
 from (

select ad.id,ad.act_id,ad.amount,ad.created_dt,ad.created_by,'max_value' as new_col
from AccountDetails ad
inner join (select act_id,max(created_dt) as max_created_dt
             from AccountDetails
             group by act_id
             having count(*) >=2
           ) as max_val on max_val.act_id =ad.act_id and max_val.max_created_dt=ad.created_dt
union 
select ad1.id,ad1.act_id,ad1.amount,ad1.created_dt,ad1.created_by,'min_value'
from AccountDetails ad1
inner join (select act_id,min(created_dt) as min_created_dt
             from AccountDetails
             group by act_id
             having count(*) >=2
           ) as min_val on min_val.act_id =ad1.act_id and min_val.min_created_dt=ad1.created_dt
  ) as tbl
group by act_id;

act_id	ini_amt	ini_dt	ini_usr	fnl_amt	fnl_dt	fnl_usr
1	10	2022-10-30	SYSTEM	156	2022-11-16	user3
2	50	2022-11-05	SYSTEM	51	2022-11-10	user2