@rr-4098, Thanks for posting in Q&A. To let users can install the web link app in Company Portal app or website, we need to assign the app to groups of users under Available assignment as below.
Meanwhile, please also set "Show this as a featured app in the Company Porta" as yes to show it in Company Portal Feature apps.
https://learn.microsoft.com/en-us/mem/intune/apps/apps-deploy#assign-an-app
From your description, I notice you assign it via Required which will not show in Company portal. Please change the app assignment to see if it can be fixed.
Hope the above information can help.
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