Adding PHP file as a panel in WordPress and execute with parameters

I’m going to create a php file with 2 loan calculators inside. This file should be included as a panel like [panel name=”calculator-main”].
On the Home Page, file should display both calculator interfaces.
On other pages – just a single calculator.

I’m thinking to display appropriate calculator on the page with the following way:

switch ($display) {
case  "calculator 1":

First calculator content

break;
case "calculator 2": 

Second calculator content

break;
default:

here come 2 combined calculators for the Home Page

}

I would much appreciate if anybody will guide me how to call $display parameter in the panel.

Thanks!