@jean-franco said:
Hi Tre and welcome here.
Select the circle (not the surface) then open the context menu (mouse right click) > Entity Info
and there you can change the segments number.
Note however that you can only do this for a limited period of time after you draw that circle. Once affected by other geometry (like PushPulling for instance), the segment count of the Entity info box will be greyed out and you cannot change it any more.
Best is to do what Alan says.
And welcome to SCF.
;9