I'm trying to work with a workflow. Where I'll use raw input as question. I want the workflow to be like first answer the question if there's answer found in knowledge base if there's no answer then use Ai Task to answer on its own like chatGPT. Need help

I am not sure if what I am about to say is fully what you want but if you want the AI task to answer the question for you, you need to turn the knowledge agent on to "Answer Manually". After that turn on "Enable Knowledge Answering" on the node with your raw input. Now go to the AI task and put in the "AI Task Input" this: Knowledge base answer: {{turn.KnowledgeAgent.answer}}. This gives the AI task the answer from the knowledge base and then you can ask the AI task to customise the answer and make it more personal or whatever you want the AI task to do. Hope this helps.

For the AI task to answer from the knowledge base answer there would need to be one. What he is asking is to use the AI task when there is no answer found in the knowledge base