Entry screen rules live inside a Web Placement's settings. In the project sidebar, open the WEB section and click Placements to open the Web Placements list. Create a new placement, or open the actions menu on an existing V2 placement and edit it, to open the Web Placement dialog. Scroll down in that dialog and expand the Entry Screen Rules accordion. Entry rules only apply to placements that point at a V2 onboarding, and you must already have at least one parameter defined in the Sources sections (URL Params, Server Data, or Variable Inputs) before a rule can read a value.