Hi Marianne :) The quickest way to do this would be to go into the folder, then click Add a New... and choose Embedded Item. Paste the embed code from google in the Snippet box and give it a name and click Add.
If you feel savvy with HTML, you can also insert the slideshow into a page. First create your page, then click the '< >' button on the toolbar. This will switch you to code view. You can then paste the code there. Switch back to normal view before saving the page. You can then add other content to the page (e.g. headings) before you save it.
To get the slideshow embed code, there should be a 'Share' facility on the google end.
I hope that helps :) Let me know if you get stuck.
Have a great day! :)
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