How to manage SQL source code that currently stored in a file server

May I have your sharing on how to manage your SQL queries in a file system across all different vendors.

I am a data analyst and I write a lot of different SQL queries everyday. They are all stand alone queries and a currently all stored in a file server. Recently, I have a problem that on a query that I developed one year ago from the file server based on the function of the query. I also find that sometime a subquery can be reused between different queries by simply copy and paste, and of course, I do have this done a few time across different queries. But my problem is I don't know how to keep track on this too.

Do you know how to do it?

Thanks in advance!