Use dynamic file for SQL query instead of static code

I am using the Power Query to get data directly from a MS SQL Server we use.

Instead of having to add the code into the window I want it to reference a separate file instead
Highlighted below is the default syntax used
Capture1.PNG

I want to replace the highlighted portion with a file path instead, or something that would achieve the same thing.

Reason for needing this, the query I use needs to be changed at weekly intervals, and once a query is placed the formatting is a mess and making changes is quite hard

Thanks for the response

That works for using files as data sources, like a CSV or something.
I tried setting this up for a SQL Server connection, syntax and setup looks like it should be working, but doesn't

An error occurred in the ‘fParameters’ query. Expression.Error: The field 'Value' of the record wasn't found.

Will keep trying to see if I am missing something