Gemini Pro mode is very good at the job. I know it’s external, but I found it convenient. It can provide advice and relate several documents. If you ask, it can generate a summary and save it to Google Docs.
By the way, slightly off-topic, Gemini is very good at deciphering documents. It even offers advice and can link several documents together (use Pro mode). It can even generate a summary sheet and store it in Google Docs, for example.