How can I deactivate automated customer account welcome email?

I’ve just been told the following by Shopify support:

Unfortunately, there is no direct deactivation button available for this notification. Instead, you can customize the email template to inform customers that they should disregard it or adjust the settings to minimize confusion or you can consult to an expert if this can be via advance coding. You can go to our community page and paste your concern there. An expert will be responding to you since that page was monitored by experts real time.

Can anyone assist?

Also, in the automated email - the main issue is it is not branded and doesn’t point to the right place. Can we change this?

I want the button to be a different colour, to be able to add images, and to be able to change where the button points. If all this isn’t possible, I’d just like to deactivate it, as my custom email already has all of this functionality.