I've never edited XML files before, I was going to edit a sequence in the highlighted mod using Adobe Acrobat (what I thought was an XML reader). I guess I clicked the wrong button because now all of my mods have the Acrobat symbol next to them. Hoping I don't have to re-download 100ish mods.
I appreciate any replies.

Right click on a file, open with> choose another app and select program of your choice, and tick the 'always use this app' button.

Thank you! Does it matter that I can't find the original app? The closest thing I have is Wordpad or Notepad. All my mods will permanently be Wordpad files now, I don't know if that makes a difference when using the mods in game?

Well, what format are they? I can't see your file extensions. Which default program is used to open a file only affects what happens when you double click on it, it doesn't affect how the file works with Sims 3.

These are my .package files and overrides in my mods folder, all my cache files have the same icon (now changed to Wordpad) as well. I just didn't want to have to download all these mods again lol. So I can edit the mods via Wordpad and just leave the mods as is because it shouldn't affect anything?

No, you don't need to redownload anything, they will work fine with the game. If they are package files though you'll need a package editor such as S3PE, as you need to extract the contents if you are going to edit xmls that are in a package.

Packages, do as @simssample said, only use s3pe. I use plain notepad for xml's.

I was meaning if the xmls are in a package file! Clarified it.

I'll have to remember that. I tend to overthink these things.
Thank you for the replies everyone! Seems like it's working fine.