It is not a reasonable scenario that an end-user can affect the reloading script. What will happen in such scenario if you have multiple end-users altering the same script? The answer is that you will have chaos. For this reason you will not be able to allow an end-user to feed setting to the script or trigger a reload.
Your screenshot shows the Input Box object in QlikView. This object is not available in Qlik Sense.
As I said in my previous comment, your scenario of having end-users alter reloads is not a reasonable scenario and will not work in Qlik Sense. This scenario will also not work in QlikView when you deploy on a server.
Please notice that I am not saying that you can not use variables and intervals in QlikView. I am however saying that you can not expect an end-user to trigger a reload or alter the script execution path. The variable changes made in webclient (IE Plugin or AJAX) will not affect the variables during reload. It works in your desktop client, but will not work when you deploy the application on a QlikView Server. From that perspective it is in most cases a bad design decision.
In Qlik Sense you can define variables in the script, but there is no native object to alter them in the app. You can however use the variables in your expression. I do not think you will be able to do exactly the same work flow as in your current QlikView implementation.
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