Keep using IE11 functionality after expiry [closed]

I am trying to understand how to keep using a legacy intranet "web application" based on VBScript (a scripting language supported by IE11, a still supported product, at the moment of writing).

I am afraid that at some point, after Windows update and the planned IE11 EoL, that intranet application will not be usable any more, so I am looking for a configuration to keep using IE11 or a migration option to a newer product. What matters to me is that it should support the legacy infrastructure.

Internet Explorer will be disabled in Windows on June 15 2022, so you technically will not be able to start Internet Explorer after this date in Windows 10 20H2+ (starting iexplore.exe will open Edge instead).

However, if your web app requires Internet Explorer, then you can configure IE mode in Edge:
Take a look at:
What is IE Mode? and
Getting started guide

Basically, if it works in IE today, it will work in Edge with IE Mode. This is not an emulation, it is the actual IE11 engine.