first time code help - PostgreSQL help

[Viji2021]

hi,

I have written code in T-Sql used code converter for PostgreSQL, got below code but it is giving complier error. I have no clue in PostgreSQL so any pointer will be of great help.
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select t.team_id, t.team_name,COALESCE(SUM(num_points),0) num_points from 
   (select team_id, host_team, 3 into team_name, num_points   -----syntax error at or near ","
                                                                                     -----LINE 3:    (select team_id, host_team, 3 into team_name, num_points
 
   from matches m
   inner join teams t on m.host_team = t.team_id
   where host_goals > guest_goals
   Union All
    select team_id, guest_team,  3 into team_name, num_points
   from matches m
   inner join teams t on m.guest_team = t.team_id
   where guest_goals > host_goals
   Union All 
    select team_id, guest_team,  1 into team_name, num_points
   from matches m
   inner join teams t on m.guest_team = t.team_id
   where guest_goals = host_goals
    Union All 
    select team_id, host_team,  1 into team_name, num_points
   from matches m
   inner join teams t on m.host_team = t.team_id
   where guest_goals = host_goals)
   r
   right outer join teams t on r.team_id = t.team_id
   group by  t.team_id, t.team_name
   order by 1

[Banfa]

That is a long and complicated statement, I would break it down and test smaller parts of it.

Alternatively rather than translation from T-SQL I would determine what I wanted to do and re-write it directly in postgresql