Adding downloaded icons and templates to library for continued use

I am really enjoying Storyline and have broadened my horizon by downloaded some of the different icons and buttons from the downloads. I now have them in a folder on my computer, but want to be able to use them as options for future presentations without having to click on it in the folder and open up in storyline each time. is there anyway to add assets to the media library (may not have the name right) or somewhere similar, so I can access for any course I create.

Want to access the downloaded icons, for example, just like I would select the ones natively on storyline.

Appreciate any help or suggestions.