New to owning my own server and would like to install the plugin but I don't understand exactly what I have to do to get this plugin to work how do edit the loot tables and make sure they work what exactly would I need to do to edit the loot table 

go to this website https://blmc.artemdanilkin.ru/ and edit the loot tables then you export and save it to the oxide/config directory

Just remember that you must have the BetterLoot plugin unloaded before you change/edit the BetterLoot data LootTables , then save and reload plugin,
Have a look at previous posts regarding this issue on plugin help page and  you will get a good idea of what you can and cannot do.