How to make silky smooth chocolate like galaxy bar or dairy milk bar? How to make silky smooth chocolate like galaxy bar or dairy milk bar from chocolate compound?
Very short answer: you can't. 

Making smooth chocolate bars is an industrial process, not replicable in the home, at least not with reasonable amounts of effort and money. You need specialized know-how, equipment, and access to the proper raw materials. 

Also, compound chocolate is not suited for making chocolate bars. It is a different end product, meant to be used as a cheaper and easier-to-melt alternative to proper chocolate bars, it is not a raw material for chocolate bars.