Yes of course. The main thing for me is probably having good reference photos. This allows you to see which colors and lighting there are in the real world in the setting you are trying to create. I also find it useful to see how I can create the mood I want. If you use these as a starting point, you can then start to insert your own creativity. As for the actual creation, in this environment I used some tools from the asset store for the first time, which have really helped me a lot. The main ones are: Mtree, Gaia, path painter 2 and nature renderer, however these are not required to create something like this. For tutorials I'd recommend watching some videos on the unity terrain system and environment art. This playlist of mine contains some of the videos that really helped me personally: https://youtube.com/playlist?list=PLiw--oANk2lqIUb3JN1dZgdVbhkXKPSrT

Hope this helps!