Raw HTML plugin, and .css/.js files

Hi, I’m currently using the raw html plugin, and I absolutely love it. It helps add raw html to your pages without wordpress messing up what you were thinking it should do. My question is that I’m not sure where to put my .css and .js file folders (or images). I know i could just put it all in one section of code, but that can get a bit messy. Someone told me i could put them in my “Media Library”, and then link to them using the URL given in the media library, but I’m fairly new to wordpress and I’m not sure what that means. Can anybody help me with that?