How to add growsurf javascript API into wix site?

Hello everyone!
I have a Wix premium website and want to add growsurf referral system into the Wix website with a form. I create a form on my homepage with a signup button.
Now I want if someone comes to me profile with a unique referral link and use form to signup on my page then referral added to my growsurf dashboard with a new user name and email.

According to the growsurf information :
Step 1: Go to your site’s Wix Dashboard , and click on the dropdown Site Actions > Edit Site.
Step 2: In the Wix Website Editor, in the top menu, click Settings > Tracking & Analytics.
Step 3: Click the blue +New Tool button and select Custom from the dropdown menu.
Step 4: In the Paste the code snippet here field, paste your campaign-specific GrowSurf Universal Code .
Step 5 (optional): In the Name field, change ‘Custom’ to ‘GrowSurf’
Step 6: In the Add Code to Pages section, select All Pages > Load code once
Step 7: In the Place Code in section, select Head
Step 8: Click the Apply button
Step 9: Based on the referral trigger you selected for your campaign, follow the specific instructions below:
I use the javascript API.
You will need to add the following JavaScript code that triggers a referral into your code. Here’s an example of using the growsurf.triggerReferral() method:
growsurf.triggerReferral(‘referred_participant@email.com’); // Example: growsurf.triggerReferral(‘jane.smith@gmail.com’)

Kindly some tell me how to complete step 9 because I don’t know about the Wix coding.
Someone who can briefly explain with coding too.
Thank you very much.:blush:

You will need to check with the service provider to find out how to get it work, since it is their instructions that you are trying to follow.