Get Random itens from a config and put it in a custom inventory (Bukkit)

Well, Hello, I'm new member here and here's my first post on a dev forum.

I'm doing a quest plugin for minecraft.

Let's go to my question, I've a config.yml file with a list of quests numbered from 0 to 5, each number is a type of quests. Example:

Quest 0 type is Mine. Quest 1 type is Farm. Quest 2 type is KillMob. Etc...

Each type have 15 different quests with a different objectives.

I wanna randomize the type and the quest itself and put 10 of them in the custom inventory I've created, how I do this? Can someone help me please? Any code you need I'll post here, Thanks!!