How do I pass parameters to my SQL statement?

I got it to work. Here is my code ( DateBegin & DateEnd parameters have been set to 'text'):

let
    StartDate=DateBegin,
    EndDate=DateEnd,
    Source = Sql.Database("this-is-the-database-url.com", "TableNameHere", 
    [Query="SELECT * FROM [TableNameHere].[dbo].[Logs] WHERE CreatedTime >='" &StartDate& "' AND CreatedTime <='" &EndDate& "' ", 
    CommandTimeout=#duration(0, 0, 10, 0), HierarchicalNavigation=true, MultiSubnetFailover=true])
in
    Source

Oddly enough, I got a bunch of error messages when exiting the 'Query Editor' (as show in my previous post) but when I created everything again from scratch, it works perfectly. 

I then saved the Power BI document as a template. When you open the template, you get prompted to enter the "DateBegin" and "DateEnd" parameters. Enter the parameters and the SQL query gets made, voila! :cathappy: