[Abin Alexander]"Hi everyone, I want to know that is there's any free vfx software like After Effects that I can use for my short film?"
I'm with Dave; I don't know for sure, but I don't think there is anything comparable to AE. In my opinion, the single best thing about After Effects is the vibrant ecosystem that's built around it: both third-party developers and end-user communities like this one. Even if you can find some free software that does what you need, it's unlikely to have the same depth of third-party developer and end-user support that makes AE great.
That said, if you're on a Mac and you have Final Cut Studio, you already have Motion, which you could use for effects and compositing. Also, there's Blender, an open-source, free 3D app, which does have a built-in nodal compositor -- though it's nothing like AE.
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