Wix lets you add custom code that loads on every page, which is all Converly needs.
Step 1: Copy your install code
In Converly, click Install in the left sidebar and copy the code shown at the top. It is unique to your site. See Install Converly for the full walkthrough.
Step 2: Add it to Wix
In your Wix dashboard, go to Settings → Custom Code and click + Add Code. Paste your Converly code, set it to load in the Head, apply it to All pages, then click Apply.

Check it works
Submit a test entry through a form on your site, then open the Activity page in Converly. If the code is installed correctly, the event shows up there within a moment.
Paste your own code
Any code shown in a screenshot is only an example. Always paste the exact code from your own Install page, which contains the key that is unique to your site.