Supply chain module

By default erpnext have supply chain module or not if not then how to get it?

ERPNext brings many data registration capabilities, e.g. including for items and their data to track, and can easily be customized to your requirements if the provided data fields are insufficient.

So do you want a specific “module” to bring or add, or are your requirements already fulfilled by what it already brings with it?

Well, what are your desired resp. specific supply chain requirements anyway?
Do you refer to specific norms for your activity domain or to specific legal texts?
Or is a more a matter of tracking batch or serial numbers for individual items?
Or do you need integration of an IoT box like a reader for RFID tags?
Or is there a need to include contracts or other paperwork into an item data store?
Do you need to track VOC fields, pharma ingredients, or climate related item properties?

As far as I can see, any of these things can be accomplished with quite standard installation and some configuration.

i want serial number / batch wise for individual items to track the life cycle of item from manufacture to it sell at any level and also costing if gst change/state change of material at any level like at any level of manufacturing.

So you want to

(1) track items individually/batch-wise across the whole manufacturing chain, or rather tree, from raw materials to finished and sold product, which includes outsourcing of parts of the overall process, e.g. for tracking, reliability and liability purposes, and
(2) calculate scenarios like “if I have this item / intermediate item produced or sold in some other state with different taxes, how does this affect its overall margins, etc.”?

Is this it?

For (1), you might want to check “Item” doctype and “Manufacturing orders” in the ERPNext documentation and maybe try out the functions in a test installation.

As for (2), I’m not sure if ERPNext does support such scenarios, maybe other forum person knows more about this.

I don’t see if you want to include external producers for intermediate steps or if this is one (big or not) manufacturing enterprise, so maybe you need some integration dev work done if external ERP systems (of other enterprises) are involved to facilitate data exchange, if tracking papers manually is too cumbersome.
I’m sure ERPNext can provide much value and provide solutions in many or all of the steps involved, depending on your scenario.