best wallpaper is vinyl but looks like Paper!
and it is pre glued 
  and then you still use glue for no bubbles
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you'll have to scrub it hard with that wall cleaner that's strong,
real strong... called TSP   but  word of warning it can burn your skin so use as directed 
 then use some dura-bond 90 for quicker drying mud
it sets up in 90 minutes  just like wood so  you can scrape it
just before (say @ 55 minutes)
 it drys to get within a 16th or 32nd  of flat then use regular
joint compound that's much creamier  after spraying it with a mist
sprayer on your hawk 

 to  finish off any low spots...  
then prime , then paint 
 .... or buy the expensive paint that has primer built into it