In order to use LlamaCloud Index in n8n, you need to create an Index on LlamaCloud.
Learn how to set up an Index through the Platform UI or from code.
The LlamaCloud index node is specifically designed for chat inputs, so you will first need to set up a Chat Trigger:
And then you can select the 'LlamaCloud' node, pasting the name of your LlamaCloud Index in the configuration field:
Once that is set, you can use the chat messages as input for the LlamaCloud Index to retrieve information simply by connecting the two nodes, and the you can start chatting: