How do I hover(3d) my fixed wing rc plane autonomously?

hqdefault
As the image shows, most of the hovering pilots do this manually.
What I want to do is simply create a flight mode that hovers autonomously. To be more specific, point the nose up pitch90, stabilize all roll/pitch/yaw angles. Then use thrust for VTOL purposes.
I am using pixhawk 4 and qgroundcontrol as mission planner. Single rotor standard plane configuration.
First post here, so if I miss something important, please warn me.