Using QUERY_STRING on CI4

I know it's not the most convenient thing, but I'm migrating an application and I need to change a lot of URLs. Being able to keep the current routing is the best option for me

What are you migrating from? An old version of CI of something else?

I never used this feature before and I'm not sure if it's still available in CI4.

The application is not based on CI3. It's a custom framework. So I was trying to avoid migrating something else.