How to finetune with a own private data and then build chatbot on that?

So far with the example of fine tuning I see examples of summarisation, chatbot based on specific use cases etc. However, I want to build the a chatbot based on my own private data (100s of PDF & word files). How can I fine tune on this. The approach I am thinking is 1-> LoRA fine tuning of the base alpaca model on my own private data 2-> LoRA fine tuning of the above model on some input output prompts.

Is it a good technique for build chatbot on private datasets. Please someone can suggest a good way of building model based on private data.