How do I get the start and end dates of the week in Postgres? (week starts from Monday)

             select extract (ISOYEAR  from fromdate_)  as year_,     --the year in which the week was made extract (WEEK FROM  fromdate_)  as week_,        --the year in which the week was made To_char (fromDate _ , ' YYYYMMDD ')  as fromdate_,  --Week start date to_char (todate_ , ' YYYYMMDD ')  as  End date of todate_       --week from   (select  (date  (curDate)  - 7* weeks_)       as fromDate_,           (date  (curdate)  - 7* weeks_ + 6 )  as  toDate_ from  ( select generate_series (1,100)  weeks_,          --  interval weeks (sequence, here take 100 weeks) cast (Date_trunc (' Week ',  current_date)  as  character varying)  as curdate --  the first day of the week on which the current date is located      )  as fg 

How do I get the start and end dates of the week in Postgres? (week starts from Monday)