Before setting up WhatsApp & Messenger widget, you need to create an account on Google Tag Manager, and link it to your store
Fill your info (Name/Email and Password) to sign up
Go to Dashboard, Choose the 1st widget by clicking on Install all in one widget
Choose Messenger/ WhatsApp/ Direct call icons (You can add also Telegram and Snapchat widgets...)
Type your Facebook page ID and your phone no.
Choose the color and positions for these widgets
Choose Wuilt, then type your domain/Subdomain and Generate Code
Copy this code
Open your Tag Manager account and click on New Tag
Click on Tag Configuration
Click on Custom HTML
Paste your code here
Click on Triggering and select All Pages
Rename your tag then click Save
Click on Submit, Publish and Continue
Log in to your Wuilt account and preview your store