I have a requirement to create Inventory in ERPNext then I will make a workflow for maintenance, the maintenance work flow will have check inventory/logistic before the company decide to buy it.
base on that what is the module can i use?
Please go through following documentations to know about stock and the inventory:
Hope this helps.
Follow the documentation provided by @shachiTakalkar to get your stock and inventory done.
After that the steps given in the manual below to setup workflow: