offers datasets. License: These datasets are exclusively available for research and teaching.
You are not authorized to redistribute or sell them, or use them for commercial purposes.
Use software (free software e.g. slicer3D or itk-snap) to segment the bones into surface models. Export as .stl files.
Import stl files into Abaqus and use as such (e.g. rigid bodies or shells) or make into a solid (quadratic tet) mesh.
But if you are a student, you better ask advice from your supervisor and/or someone around who knows what to model, and how.
Unless you can purchase it from a company (or your boss establishes a collaboration with a lab that has an FE model of the pelvis), you will have to make it yourself.