I can't add mods, they're not folders, they're just files. If anyone knows a way to solve or can help me fix this problem, please let me know.

Sounds like you need to download 7 Zip. Generally, when a modder releases something he or she will compress it into .zip, .rar, .7z or possibly .ace format. If you download from the Japanese community the format might be .lzh. I am pretty sure that 7zip can open all of those, but if not you can always google the file extension and find out what opens it.

The reason for zipping is to keep all files together and importantly to save space. My largest mod is over 900mb when uncompressed and is around 300mb when compressed.

Edit: If I am misunderstanding and you are opening compressed files to find other files with extensions of .bsa, .esm or .esp, those just go in your Data directory as-is.

Well, i have WinRAR to unzip items but in the data folder doesn't contain the normal "meshes" or "textures" folder, it just has them saved as a file.

Is it just an .esp file? It may be a mod that doesn't replace any textures or meshes, if that's the case all you need to do is place the .esp in your Oblivion Data folder and check it before you start playing.

I have a set of help files for people who are new to mods. It takes you from downloading through getting the mod working in your game. It includes an extremely simple and useless mod That you down load, unzip using 7-zip and install, then activate and test. If you are interested, click on the highlighted text below to be taken to the site.

http://s1.zetaboards.com/TheStormRavenLibrary/forum/256092/

Thank you Bben46 but Palpenious, my "meshes" and "textures" that are already in the oblivion data folder .esp files not folders and i don't understand how i'm supposed to download a mod and use it on oblivion.

Which mod are you trying to install? Or at least if you could give one example maybe we could see what it is that's giving you trouble.

It's basically just about all mods that require you to put something in the data folder/meshes folder/textures folder. My meshes is titled "Oblivion - Meshes.bsa" not quite sure where to put the items that i've already downloaded(esp files).

Ok I see your problem. That file is just part of your default Oblivion install. Inside the same directory where that is (Data) create a FOLDER and name it "Meshes" and another and name it "Textures." After you do that, you can just open your mods, and drop the files into your Data directory. Usually your zipped mods will include a meshes and textures folder and you can just put them into "Data" and they will overwrite what they need to. .esp files do not go into meshes or textures folders, but into the main data directory.

Hello reborntoninja, if you are still having trouble installing these mods, then, if you want, I can create a screenshot tutorial kinda thing that will tell and show exactly what you need to do step by step if you tell us what mod you have downloaded and are trying to install.

Omg Thanks So MUCH!!!!

I think SavageArtistry kind of summed it up.

Un-zip the files to a temporary location. Create new folders called 'Meshes' and 'Textures' in the Oblivion/Data folder and copy/paste the files into the right folders. ESP files go straight into the Data folder, as do BSA.
To activate the mod, go into 'Data Files' in the Oblvion Launcher and check off the ticky box next to the mod name.

Simple as that, eh?