Find a local design store or wallpaper store that has all the wallpaper books. Plan on spending a few hours looking through the books. If you live in a major metro area you might have a large Design Center that you can visit. Many are to-the-trade only, but will allow customers to walk through and browse. These are a great place to see wallpaper because the manufacturers will have their own showroom with large sample boards hanging on the walls for you to flip through. For example, in Los Angeles the public can walk through the showrooms at the Pacific Design Center.

https://casoca.com.br/revestimentos/revestimentos-de-parede/tecidos-para-parede/tecidos-para-parede-natureza.html

Instead of wallpapering, I’d avoid the trouble and cost, just paint a great paint color and add colorful curtains to hide the clothes. Add a large piece of art on the far wall and unique lighting in ceiling. It will be a lively space and if landlord requires, slapping on white paint before you move is pretty easy. Also replace lighting to the original and take your light with you.

That's a beautiful mural, and looks to be custom made, perhaps by hand? Check out this site: https://www.photowall.com/us/wall-murals/nature/forests-woodlands They have thousands of murals and the link is to "forest/woodland" scenes. Prices range from $3.50 to $4.50 per square foot, so an 8' high wall 10' long would cost around $320. Depending on the size of the room, and whether you are doing one wall or all four, it doesn't seem like the price would come anywhere near $7,000. You won't get the exact scene but some are very close.