Hello Vinay,
I recommend you follow the guide to getting access:
Limited access to Azure OpenAI Service
https://learn.microsoft.com/en-us/legal/cognitive-services/openai/limited-access
Registration process
Azure OpenAI requires registration and is currently only available to approved enterprise customers and partners. Customers who wish to use Azure OpenAI are required to submit a registration form.
If this is helpful please accept answer.