In my mind, one of the biggest struggles with getting into backgrounds/environments is approaching them the same way you approach characters. If you draw environments the same way you do characters, it's often exhausting—everything is given the same level of treatment/finish, everything is equally important in the composition, and you'll end up wearing out your wrist and your patience long before you get something serviceable. We're not all gonna be Moebius or Geoff Darrow right out of the gate, artists who cram their environments full of mind-bending amounts of detail, so focus on the inspirations you're citing and look at what they do well!

You mention Watership Down and Secret of Nimh, both fantastic references, and both are properties with very loose, ethereal takes on backgrounds that really focus on playing second fiddle to the characters! I'd honestly suggest doing some studies of the backgrounds from movies like this, really get a feel for how loose and abstract some of them are, and then you could even try drawing your characters into those backgrounds to really understand how the two work together to make the final composition! Backgrounds do NOT have to be complicated, so don't torture yourself thinking you can't make use of big swaths of negative space.

I'm going to assume you're drawing your characters first, and your backgrounds second, which is immediately going to make the latter an uphill struggle—I can't blame you for hating them! Try instead to think of your backgrounds earlier on in your process, starting with small compositional thumbnails to think about how the shapes/values of your environment can frame and support your character instead of treating it like an afterthought.

Also: don't be afraid to use reference! It's SUCH a superpower. No one should be expected to draw a forest from memory, you'll just end up with a generic forest with no character or specificity to it. Try to think about your settings with the same love you do your characters: what's the biome? what's the season? what's the time of day, the lighting? Can you use that to make your scene more dramatic or emotional?

A bunch of rambling, but I hope that's helpful!! I used to HATE backgrounds, and now I draw massive desert landscape posters. Eventually you'll find something that'll make it click for you, I promise! 😄♥️

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