Are you required to use Descarta2D? A quick search makes me think it's probably defunct or at least not supported in recent versions of Mathematica.

The basic, built-in graphics capabilities of Mathematica can easily show points, circles, and lines. If you can be more specific about what you want to see, I'm sure someone can help.

I'm using Mathematica version 13.1. I don't have Descarta2D. I'm not going to install Descarta2D, and I am not going to install version 6 of Mathematica. If you want guidance on how to do this in "vanilla" Mathematica (i.e. without Descarta2D), then I can provide guidance, but there may be slight adjustments required to be compatible with V6. Otherwise we'll just hope someone else on this forum has the necessary prerequisites installed to be able to help you.

Not directly related, but does your college provide Mathematica licenses to students or some computer lab where you can use Mathematica? If so, you can use a newer version of Mathematica. Or you can upgrade at student prices.

Also not directly related, but I'm very surprised that your school is requiring you to use such an old add-on. Are you really sure that you're being required to use Descarta2D?