How to make excel populate form documents

Hello, Reddit. I work at a law firm in the Midwest and recently mentioned in a group chat that I’m interested in AI and have been playing around with it in my free time (honestly just ChatGPT so far). My 67 old boss saw that and told me he has a “firm project” for me. He said we use a lot of form documents and motions that could be automated and asked me to figure out how to do that.

As a first year lawyer, I said yes… but I have no idea where to start. The only thing I can think of is something we used when I worked at legal aid in law school. We had an Excel sheet where we entered client info, and it would auto populate multiple Word documents at once. There was no AI involved, just templates and Excel.

Can anyone point me in the right direction on how to learn this or what tools I should be looking into? Even a good YouTube video or beginner resource would be really helpful.