The phrase "to hang the paintings" means to place or attach the paintings on a wall using hooks or nails, so they can be displayed and seen. Full definition
The gallery hung the painting on a wall built for the exhibition. (artbusinessnews.com)
Some art museums have returned to the earlier custom of hanging paintings in a tiered arrangement in order to exhibit more of their works. (britannica.com)
If you want to put something in the wall of your bedroom, just hang a painting with beach theme. (erahomedesign.com)