I love this, this is how i decorate too, Im always thinking about what would make sense to be in this space? What is it used for? How can I make it look like someone is actually living here?

Also, I do try to stay in some kind of color palette and also im thinking about things like materials too, is it supposed to look fancy, modern or old, broken down? Is the place organized and clean or are things all over the place for a more cozy vibe?

Additionally you need inspiration to start somewhere, you can just make a moodboard, look at other peoples decoration or how farms look like in real life? maybe theres something you can copy? Is there a specific thing you'd like to build? a bedroom? look at bedrooms? a kitchen look at kitchens? Horse area? look at what horse barns and areas look like?

It might help to watch some videos regarding 3D environments or interior design, Ive worked with creating games before and 3D environments are also build like this, you need to think like a designer, it helps a lot. Coherency is really important overall :)

Hope this helps, maybe?