How is it messed up? Damaged with holes? Lumpy? Stained?
Hello could you possibly post a photograph to better see your situation and area of damage? Having a visual might be best guidance to a help find the best suggestions or potential solution to best know what you are dealing with.
A photo would help.
A picture would help tremendously in determining the best option but what about covering it with plywood, you could do strips to make faux shiplap or solid plywood pieces to cover the wall. Maybe even concrete coat it if you like that look! There are many options if you could just let me know a little more about the damage you are trying to repair/cover! Have a good one!
Hi Vilma: You can use a wallpaper, probably with a raised pattern if the wall is really rough. If your wall has gouges, fill them in with spackle first and let it dry really well. Or, you can use a textured paint. Good luck
skim coat it https://www.youtube.com/results?search_query=diy+skim+coat+walls or use textured paint https://www.youtube.com/results?search_query=diy+texturing+with+paint