By following this youtube tutorial: https://www.youtube.com/watch?v=1J4r0mt9zz0&t=5s I got to make this cave. Really helpful in seeing how a lot of aspects in Blender is working. Getting aquainted with everything from reallife scale, seeing how textures makes such a big difference on a simple mesh, uv unwrapping, lighting, materials (both emission and diffuse), particle systems and more.
Thank you very much - Yes I really loved it too. It's so varied and you get a really cool render in the end. :)
I really like this tutorial by Andrew Price. You have executed it well. Nice render. :-)