I’m trying to download mods to my Xbox using horizon and I’m very very new to this and I’m having stfs problems the .exs or whatever that kind of thing is called is a .rar and idk what any of that means but I jus want my mods can anyone help?(it’s for Skyrim btw)
.rar is a compressed archive. You need to extract the file from within the .rar archive before you can try to do anything with it in Horizon.
But there’s also another issue. If that .exs file is not a valid Xbox type of file than Horizon can’t help you. A lot of people assume that they can use PC Skyrim files on an Xbox and just add them with Horizon and that is just not possible. Feel free to link to where you got the file/mod from and I will take a quick look for you.
I got the link from xpgamesaves.com and I was just downloading random mods to see which ones worked and all of them were .rar
As @SteveWonda said, .rar files are compressed archives. Similar to .zip files. You need to extract the contents of that file like you would with .zip files.
Windows 10’s own built-in extraction tool isn’t the best when it comes to .rar files. But there are free alternatives.
Two free tools you can use to extract .rar files are:
- RAR Extract Frog (https://www.philippwinterberg.com/software/free_rar_extract_frog.php)
- 7-Zip (https://www.7-zip.org/)
Choose one. Install it. Right-click the .rar file, choose the RAR Extract Frog or 7-Zip option (whichever you installed) and then extract it.
I personally use 7-Zip, but someone who isn’t so tech-savvy would probably prefer RAR Extract Frog. 
Thank you very very much!! 
might not understand how exactly to do any of this but I sure am gonna try to figure it out
When I instal these will it help convert it to the correct file to plug into horizon? And do you know where I can find any good mods/gamesaves to try and mess with?