If you are planning 3D designs, Fusion360 takes a bit of getting used to but is extremely powerful.
https://www.autodesk.com/products/fusion-360/
You can register for a free hobby license for the scaled down version, or a free educational license of the full version. It has good CAD capabilities and on the CAM side can generate g-code for 3D printing and CNC, or else allow you to export STL models direct to a slicer.
That sounds awesome. I've never used CAD software but I might as well start, and also I have access to a 3d printer, so I might as well learn something for that as well. I'll give it a try!
My ADHD don't need no plannin'
Yeah I'm here like "… you folks are planning?"