If you are looking to convert your Adobe Illustrator file to an OBJ format for 3D modeling, there are a few steps you can follow to achieve this. Illustrator is a powerful tool for creating vector graphics, but it does not have native support for saving files in the OBJ format. However, you can use other software to convert your Illustrator file to OBJ. The process involves exporting your artwork from Illustrator and then importing it into a 3D modeling program to save it as an OBJ file.

To start, open your Adobe Illustrator file and make sure that your artwork is complete and ready for conversion. Once you are ready, go to 'File' and select 'Export'. In the export window, choose a location where you want to save your file and select 'SVG' as the file format. SVG (Scalable Vector Graphics) is a widely supported file format for vector graphics and can be easily converted to other formats.

After exporting your file as an SVG, you will need to use a 3D modeling program such as Blender or 3ds Max to import the SVG file and save it as an OBJ. In Blender, for example, you can import the SVG file by going to 'File' and selecting 'Import' > 'Scalable Vector Graphics (.svg)'. Once the file is imported, you can convert it to a mesh and then save it as an OBJ file.

In conclusion, while Adobe Illustrator does not have native support for saving files in the OBJ format, you can still convert your artwork to OBJ by following a few simple steps. By exporting your artwork as an SVG from Illustrator and then importing it into a 3D modeling program, you can save it as an OBJ file for use in 3D projects. This process allows you to leverage the strengths of Illustrator's vector graphics in 3D modeling projects.