For each artist, count how many songs.
select t1.artist_name, count(*) from artist as t1 join song as t2 on t1.artist_name = t2.artist_name group by t2.artist_name
Among those, only count the Bangla songs.
select t1.artist_name, count(*) from artist as t1 join song as t2 on t1.artist_name = t2.artist_name where t2.languages = "bangla" group by t2.artist_name
Which is the top one artist who has the most counts?
select t1.artist_name from artist as t1 join song as t2 on t1.artist_name = t2.artist_name where t2.languages = "bangla" group by t2.artist_name order by count(*) desc limit 1
How about top 3?
select t1.artist_name from artist as t1 join song as t2 on t1.artist_name = t2.artist_name where t2.languages = "bangla" group by t2.artist_name order by count(*) desc limit 3