Use url parameters in checkout page

Hey guys, newbie here.

I wanted to ask if you can use url parameters in a checkout page? For example, mydomain.com/checkout?item=1

I have 3 items in my sales page all redirecting to the same checkout, but I have a script that captures the parameter value and checks the corresponding radiobutton in the product-list module. But the issue is that the order summary and order bump modules are not showing when I have the parameters in the url https://i.imgur.com/hSI9sdl.jpg. Without those parameters, they’re showing just fine https://i.imgur.com/PIPfkQp.jpg

Any idea how to go around this?

Thanks much!