At present this is a manual method that can only be completed one by one. Save the texture to your computer, by right clicking and selecting "save as" or dragging it across to your desktop etc. In SketchUp, go to File > Import > Select the image and choose "use as texture" in the dropdown box. You can then place the texture onto the surface you want, and it will appear in the materials library for that file. You can then right click on the surface, select Texture > Position and use the handles to adjust the size, orientation and position of the texture on your model.
I am not aware of a way to permanently add a texture to the sketchup materials library, but maybe this is possible - try googling it on the web.
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