Configure Marlin on Octopus Pro

I have a Bigtreetech Octopus Pro running a custom concrete 3D printer and I need Marlin up and running cleanly on it. The board is installed and powering up; the gap is the firmware. Your task is to... (Budget: ₹1500 - ₹12500 INR, Jobs: 3D CAD, 3D Printing, Arduino, C++ Programming, CAD/CAM, Electronics, Embedded Systems, Microcontroller)