To get started with building your own integration with an ERP from scratch, you will need to utilize the Shopify Admin API which is available in both REST and GraphQL. This is the API that will help you create, read, update, and delete properties associated to your Shopify store including Products, Orders, Customers, Discounts, and much more. You can use this API to integrate with your ERP's own API in order to import/export any data you need.
Alternatively if you do not have the resources to build your own integration from scratch using the Admin API, you could always look at the Shopify App store to see if there is an app that could assist with integrating with your specific CRM or hire a Shopify expert to help build this integration for you.
Hassain | Developer Support Specialist @ Shopify - Was my reply helpful? Click Like to let me know! - Was your question answered? Click Accept as Solution