First off, is this the first time you've installed Liberty or Death? If it is, you need to install the full version first; what I released recently was just a patch. You can find the full installer here: https://www.mbrepository.com/file.php?cid=1&id=694
You'll want to extract both the full installer and the patch to your C:\Program Files\Mount&Blade\Modules\ folder. When you do so, a folder should be automatically created inside of Modules called Liberty Or Death that has all the mod files in it.
After these things, you should be able to see Liberty or Death on the M&B startup menu.