LearnToMod is always adding new content, though there are some Minecraft blocks not in our blockly menu yet. Say there's a block you want to use that you can't find in our software -- if you know the Minecraft id number of the item, entity or mob you can summon the item by writing it into your code. For instance, there's a different id number for purple wool and orange wool.
Here's where to download Minecraft -- Right now LearnToMod is only compatible with regular vanilla Minecraft that is Mojang authenticated.
The Server Admin page covers how to log in.
The Run Your Mod badge explains how to locate your mod chest in Minecraft and how to run your mods.