Thank you for reaching out Microsoft Q&A forum!
Based on your query, it seems that you are having trouble finding the custom avatar key after signing in to the Speech Studio.
Once you have signed in to Speech Studio, choose the desired avatar model (either Text to Speech Avatar or Live Chat Avatar). Then, navigate to the "Next Steps" tab and scroll down to find the Resource Key as your avatar key. Alternatively, you can also find your avatar Key by going to the "Keys and Endpoint" option under the "Resource Management" tab. See the screen shots below:
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I hope you find the information you are looking for. If you need any assistance, please don't hesitate to contact us. Thank you.
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