What furniture do I need to cover up plain walls?

Living Room Furniture https://www.arturest.com/

Home improvement services from https://ldesign.studio/

Try cheap art......

It is depends on your cost. 

Depends on how heavy the furniture is that you want to hang, which will determine brackets and other fasteners. That a good answer, Mr. Troll?

That's unfair previous anon.  Kevin here has special educational needs.  A classic troll posts in order to deliberately wind people up.  Kevin can't help it.  This is his "special subject."  We should all be thankful that it's a harmless one and either ignore or indulge him if you feel like it.  It's the asking that's important to him.

Troll poster, check his other questions. all about rooms he wants to decorate but never does. 

You do not use furniture to cover up walls.  You use art.

Check out Louis Leonard Art, art.com and Wayfair ...

Narnia-sized wardrobes.

Tall bookcases.