[Ram Prajapati]"i am new to this forum and also new to motion graphic world... can anybody give e suggestion how to make that bubbles of that video?"
You can do this with shape layers and expressions. The idea is that you animate one main "leader" layer, then link the properties of the other "follower" layers to the leader. A change to the leader will then affect all.
However, if you are new to After Effects, that's going to be a lot a take in. You have to learn to walk before you can run. I'd recommend the following link, in which Adobe's Todd Kopriva pulls together some important introductory materials:
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