Is there an Open Source 3d designing tool?

Is there an Open Source 3d designing tool? Something to make my designs and get the STLs?

You can try with: Freecad or Sketchup. Easily with online aplications like Autodesk 123Design or Tinkercad. Good luck!

There are a bunch. I use OpenSCAD, which has a programming-like interface that I like. Blender is another OSS product for more organic type drawing.
There’s also Sketchup, AutoDesk123, TinkerCAD (online), and a ton of others that I’m not sure are OSS, but are definitely free.

Depends what you need. Currently, I use Blender for “Artistic” designs and Openscad for mechanical pieces

Mostly technical stuff and less artistic

Mostly technical? Autodesk 123D Design and DesignSpark Mechanical (by RS Components). Not Open Source, but available for free…

And also Creo Elements/Direct Modeling Express. This is pretty potent, but limited to assemblies of 60 parts

@Richard_Tegelbeckers thanks will dig into all

The best parametric open source software I have found would be Freecad. Blender is very powerful when working with mesh files.