SCM is like Master level, which covers activities of logistics general and Logistics Execution. In simple, in a corporation, SCM (Supply Chain Management) integrates the resources of both manpower & materials/services to a method and execute the activities ranging from supplier to customer. Strategic activities (like Forecasting/Demand Planning/Safety Stock) & Operational level activity results with increased productivity & Profitable.
SAP MM is an important part of the Logistics Area and the finest functional module in SAP ERP, hope you are doing research to get a start.
SAP MM is central to Manufacturing & Trading Industries, it forms the internal part of the complete Supply Chain Management.
SAP mm has some core Core functions & some Central functions. Core functions are specific to a specific module. Purchasing [Procurement - Sourcing of Materials/Services to be procured] is that the core of SAP metric linear unit, Inventory Management, Valuation [MM-FI Integrations], Consumption-based coming up with, Invoice method, Special sort of procurement are the business process relies with SAP MM.
SAP MM interview Question: https://intellipaat.com/blog/interview-question/sap-material-management-interview-questions/
In SAP R/3, in particular to SAP MM, It's about
1. Master Data’s [Material Master/Vendor Master/Service Master/Source List, Info-record & Quota Arrangement]
2. Transnational Data’s [Transactions to hold out Procure-to-Pay method & Inventory Management, Account Determination & LIV Process].
And, you cannot transform yourself into an SAP MM Consultant over a day, it needs consistent efforts in many behaviours like below,
Mapping business requirements for SAP capability
Knowledge of SAP module (i.e. MM) in both transaction and configuration (but not only this). you need to learn the way to build test scenarios, train users, understand integration concerns like cross-functional modules like MM-D, MM-FI, MM-PP etc.