Hello and thank you for answering. I believe the gears are composed of thousands of tiny curve segments as you said. As you can see in the photo all the curves are composed like this. That's why the program freezes. I left it running for 20 mins just in case and nothing changed.
Yes I can use the patch fill, it takes 3 mins to load, click the checkmark and I get this result/error: "Could not replace faces with a single face"
Before:
After:
Now for design modeler, I tried importing the file but it doesn't work there as well. For "Attach to Active CAD Geometry" I click it and then for source I put the DXF file and click generate and then I get those error messages: "No compatible interface found for this file type", "Geometry Interface not found", "Attach failed". For "Import External Geometry File" I get the same ones. My configuration manager looks like this:
For the gears, i don't think their curvature is complex, I am using those measurements:
From this website (https://evolventdesign.com/pages/spur-gear-generator). Now I was planning on creating them yes, but for my thesis I will need to run simulations on different tooth counts and different pressure angles as to get a variety of data. If it was just 2 gears I would have created them yes, but since a variety will be needed that's why I wanted to go with a spur gear generator website, to eliminate the time needed to create all those different ones and yet I am nowhere near close haha...