You don't need to convert your data to a usable format. In order to use your GPX files in one of the mentioned programs, you can export your data from the Geo Information Manager to an usable format. Before you can do that, check the following file for the compatible files types that can be imported in ArcMap program. Also, you should check the following support website of the AutoCad program for the same reason. After you did this, open your application, tap on GPX Import Export, choose export and select a suitable format that can work with one of the mentioned applications.