This needs Wix’s Custom Code, which is on paid plans with a connected domain. It’s not offered on a free wixsite.com address.
- In your dashboard, go to Settings → Custom Code.
- Click + Add Custom Code and paste the Snippet in.
- Set “Add Code to Page” to All Pages, and “Place Code in” to Body - end.
- Apply, then Publish your site. Custom code doesn’t run in the Editor’s preview.
Your line
<script async src="https://cdn.sitepets.com/v1/pet.js" data-key="sp_YOUR_SITE_KEY"></script>
Once it’s live, Claim your Pet from the browser you copied the Snippet in.