yes, you can, but the images on that site are composite images; including a diffuse map (jpg or png) as well as displacement maps (bump maps, normal maps). It looks like he provides a bunch of other texture mapping files as well which afaik, Fusion does not support. I'm not a rendering master, so there may be a better way to do this, but you'll need to find a texture in the Fusion library that has a normal map in it ( a lot of the wood textures do) and save a new texture. replace the wood textures, with the diffuse, bump & normal maps in their respective places in the texture dialog & you should have your new texture ready to go. tweaks will probably need to be made!
Check out the HDRI part of that site too for some great lighting setups!
