Thanks for posting!! I love the minimalist look, and it’s definitely super achievable with a few small touches!
If your walls aren’t white, I would recommend painting them a white or close-to-white color to cover your room in a fresh, clean brightness. That window sounds beautiful! Depending on the height of the window, it could be really cool to put a bench underneath it that you can add pillows or plants to. (Kind of like in Eva’s room, except her bench was built-in!)
As far as your floor, I would see the carpet could be covered up by a nice white shag rug before you spend the time and money on redoing the whole thing! Just covering up some of it could really change the room, and you’ll notice it a lot less!
For your storage bed (which, by the way, is such a good idea for a minimalist room to keep the clutter at bay!), I have found good, affordable options at Wayfair or Ikea. A thing to keep in mind is to make sure that the drawers are sturdy. I also suggest getting a headboard to anchor the bed, since the storage bases can look very bulky and out-of-place without a headboard to balance!
Good luck with your room! Let me know if you have any more questions!