Multiple independent scenes rendered to textures?

Hello I am currently looking into rendering engines for some software for work, and Stride seems like a very good option thanks to being completely open source and uses C#, however I have hit a bit of a roadblock.

The actual rendered output is not intended for the screen and is instead being sent to some custom hardware and/or turned into a live video stream.
I presume this is possible to do via render textures, there is another discussion talking about how to save a rendertexture to a png file but it does not explain when the correct time to call this would be, how do I do this after the texture has been rendered to completely?

We would also like to be able to render multiple independent scenes into different textures, rather than different views of the same scene, and then displaying these in a picture-in-picture or in a grid on the screen, would this be possible in Stride? And if so how would I go about doing this?
The closest I have been able to determine would be to load the different scenes as child scenes and use a different render mask for each child scene