Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
If I understand correctly, you want to add QnA maker to your azure web appwithout using Azure Bot Service?
Yes , this is possible. please take a look at this Azure doc for more infomation: Plan your QnA Maker app
The App service is used by your client application to access the published knowledge bases via the runtime endpoint. App service includes the natural language processing (NLP) based second ranking layer (ranker #2) of the QnA pairs at runtime. The second ranking applies intelligent filters that can include metadata and follow-up prompts.
To query the published knowledge base, all published knowledge bases use the same URL endpoint, but specify the knowledge base ID within the route.
{RuntimeEndpoint}/qnamaker/knowledgebases/{kbId}/generateAnswer
Please note: The QnA Maker service is being retired on the 31st of March, 2025. A newer version of the question and answering capability is now available as part of Azure Cognitive Service for Language.
Hope that helps. Let us know if you have further question.
Best,
Grace