This comprehensive guide provides an in-depth exploration of Business Central Administration and Automation APIs in Microsoft Dynamics 365 Business Central, specifically designed to help developers, administrators, and consultants master programmatic environment management and automation for the MB-820 certification exam. The guide systematically covers both the Admin Center API (for tenant-level operations including environment management, telemetry retrieval, and Application Insights configuration) and the Automation APIs (for company-level operations including company creation, configuration package deployment, extension management, and user provisioning), explaining their authentication mechanisms, endpoint structures, and asynchronous operation patterns through real-world examples extracted directly from the Business Central System Application and Base Application. Special emphasis is placed on the infrastructure-as-code approach—utilizing PowerShell scripts and CI/CD integration to achieve repeatable, standardized tenant provisioning—along with advanced topics including the four-stage configuration package lifecycle (Create → Upload → Import → Apply), Extension Management codeunit (2504) for programmatic extension deployment, Security Group management for role-based access control, Azure Application Insights integration for long-term telemetry storage, and the Business Central Performance Toolkit (BCPT) for load testing with concurrent virtual users. Each concept is reinforced with practical code examples from Microsoft's own implementations (APIV2 automation pages, Config Package Management, and Extension Management codeunits), complete PowerShell automation workflows, error handling patterns with retry logic, and targeted MB-820 exam preparation materials including key concepts to memorize, 10 hands-on exercises with solutions, 10 practice questions with detailed answers, and a summary of critical best practices for professional Business Central administration and DevOps automation.