If you plan to animate these '4 wheelers' in your video, then you will need a 3d modelling app such as 3D Studio Max or Maya, you need to build your models in the app, rig it with a skeleton and then animate the skeleton using keyframes. That's a lot of work to say the least and more so if you have never used a 3D app before and then use an alpha channel to composite it into the video (background plate).

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