How can I use language models with 3rd party voices?

There are few language modles in Elevenlabs, and I wanna try test using other language models not multilingual.
By the way, I found on My voices, If I use 3rd party vocies and make its voice ID, then it just shows me multilingual language model.
I would like to manage this process form within my app using these APIs.
Your help would be greatly appreciated!
Thanks.