How to get (subscribe to) waypoints + ROI from the mission?

Hi everyone. I use bundle of MissionPlanner + Mavlink + MavSDK + compute module. I need to customize the process to subscribe/get info from autopilot about waypoints + ROI to make certain actions by compute module & servo drives. One waypoints are just waypoints, other waypoints - call-to-action with servos. In order to distinguish them, I was recommended to use ROI. But I dont see simple options to subscribe to any messages to get info about waypoints & ROI from Mission Planner to autopilot & MavSDK & Mavlink - to me (compute module). Will be very grateful for any recommendations.