You have no functions in your select that use a group by.
If you just use the ORDER BY, you are on the right track.
If you really MUST have a group by, you will need to do something like:
SELECT a.1, a.2,a.3,COUNT(a.3)
FROM atable a
order by a.1
group by a.1;

By having an aggerate function in the select, it can then group. In Oracle GROUP resets an aggerate funtion.