CALL OF DUTY MODDING
Hey Superblake, welcome to DEVRAW!
If you joined the discord you could've @'d any of our Admins, they'd be glad to help, but I also don't mind giving a quick rundown right now.
On the releases page, you can find all releases/assets/textures/perks/etc. that you can add into your map or mod. All you have to do is click on which item you want and it'll bring you straight to a download page.
After downloading your asset, open it up, and there will be a "readme" or an instructions page in the download that explains exactly how to install it.
I hope this helps!