If you are looking for a simpler way of implementing this feature (which is usually referred to as “click to text” or “click to sms”, then you can skip the first six steps on your list and use simple html to trigger the action via an iFrame.
Link to test: https://www.velo.totallycodable.com/test-click-to-open-sms
If the user has a messaging app on their computer / laptop it will simply prompt permission to open it.
Or you could always hide it using a little code to detect if they are on a mobile phone or not.
https://dev.wix.com/docs/velo/api-reference/wix-window-frontend/form-factor