Creating a .swf File Link and finding an .swf File
So you need an .swf File but you don't have one? Or do you need help uploading and getting a link for your .swf File?
Well look no further than reading this quick guide on how to do so!
I recommend searching on google for the .swf file for example "pc breakdown swf file download" will mostlikely find you a result.
Here comes the trick part. Make sure that you have a GitHub account (this site) (i will add alternatives in the future) and go to this page: Create a New Repository then give your repository a name 
Next, go to github.com/YourUsernamehere/YourRepositoryNamehere
⤴ Put your username there ⤴ Put your repository name there
Next drag the .swf file in there and click commit changes.
Now all you gotta do is know the name of the .swf file in my case its PC Breakdown.swf.
Next you gotta create a page so the script can access the file. To do that go on github.com/YourUsernamehere/YourRepositoryNamehere/settings/pages
click on Branch, select main and click Save 
It will now say "Your site is published at [...]" copy the sites name and open it in your desired Web-browser.
It'll say that an 404 error has occurred but don't worry, click on the address bar and type your .swf files name in there like this:
Copy that sites link with the .swf file at the end (the link should look like thisyourusername.github.io/yourrepository/Yourswffilehere.swf) and open (edit) the script/code. Go to the line "INSERT SWF FILE HERE" and put the link you just copied there in the "____" for example "https://happygamer1450.github.io/gsitesswf/PC%20Breakdown.swf" And save or copy the code/script.
To use it on your Google Site site go to this wiki link: Using the Script on your Google Sites site - Wiki
Well you did it! Wasn't that hard heh?