drawing an exact size circle

I have Corel Paint Shop Pro x64  I do graphic stuff mostly for my own amusement and entertainment. When I hit a problem I try to find the answer online. I have often noticed my program layout doesn't look like any I see on turtorials or help pages. I've even reset it several times and still not like what I see other people post.  I am desperate. I need to draw and exact size circle. Help pages show a box/es for inputting the exact diameters but my ellipse tools has only the radius and center boxes. Where and or how do I get the options to input exact diameters?