This paper presents the development of an autonomous drone system integrating a Pixhawk flight controller with a Raspberry Pi 3B+ companion computer. The system enables live video streaming, autonomous navigation, and real-time control through MAVLink communication via the Telemetry 2 port. A ground station connected through WiFi/LAN allows for remote mission control and monitoring. The implementation includes MAVProxy and a Flask-based GUI supporting autonomous flight operations such as takeoff, waypoint navigation, altitude adjustments, and landing. GStreamer facilitates low-latency, high-definition video streaming from the Raspberry Pi camera to the ground station over UDP. The architecture optimizes command execution, telemetry data management, and real-time decision-making, enhancing autonomous flight efficiency. Testing evaluated navigation accuracy, video transmission latency, and network reliability, identifying areas for improvement in communication resilience and computational effectiveness. The research highlights processing limitations of the Raspberry Pi 3B+ when handling multiple autonomous tasks simultaneously. Security vulnerabilities in telemetry data and video streams are addressed, with encryption strategies proposed to strengthen data protection. Performance comparisons with existing solutions identify opportunities for improvements in latency, reliability, and computational efficiency. This research contributes to UAV technology advancement by providing a scalable, open-source, and cost-effective autonomous drone control system, establishing groundwork for AI-powered navigation and secure UAV operations.