How are you looking at integrating it presently, have you been given a chunk of html code to add to your site?
https://support.wix.com/en/article/using-iframes-to-display-visible-content-on-your-site
https://support.wix.com/en/article/embedding-custom-code-to-your-site
If you have then note that Wix won’t support code from third party providers and for more help with this you would need to go back to Pollfish and ask their own support.
Wix does not provide support for technical difficulties associated with third-party code snippets. If you are experiencing an issue with your code snippet, please contact the provider directly.
You would probably be best using their own API with Wix.
https://www.pollfish.com/docs/api-documentation
https://www.wix.com/corvid/reference/wix-fetch.html
https://support.wix.com/en/article/corvid-accessing-third-party-services-with-the-fetch-api
https://www.wix.com/corvid/reference/wix-http-functions.html
https://support.wix.com/en/article/corvid-exposing-a-site-api-with-http-functions
Exposing your Wix site examples.
https://www.wix.com/corvid/forum/corvid-tips-and-updates/example-myapi-and-myapiclient
https://www.wix.com/corvid/example/exposing-apis