Commercial and proprietary software like Adobe Illustrator, Adobe Photoshop, and CorelDRAW let you view and edit AI files. However, to edit AI files for free, there are not many options.

About View the 3d models, from the files: Wavefront OBJ, StudioModelData SMD, Re4 Uhd BIN, Re4 Ps4/Ns BIN, Re4 PS2 BIN, Re4 2007 PMD, and your Re4 Scenario SMD files (PS2/UHD/2007/PS4/NS).