how to dynamically add a customer's address in a mail after they purchase a product from a wix website? I have attached other dynamic value.

This forum is for all code related issues on your website.

You are using Wix Automations which are not code related.
https://support.wix.com/en/article/adding-dynamic-values-to-emails-sent-from-wix-automations

However, it does state at the bottom of that page a workaround for you.
For Corvid by Wix users:
If you’ve enabled Corvid , you can use data from customs forms made with Corvid by Wix as variables in your email. This is an advanced application. Learn More

If you are using the Wix Stores app, you should be going through Wix Support for more info on this or reading through Wix Stores own support pages.
https://support.wix.com/en/article/contacting-wix-support
https://support.wix.com/en/article/sending-confirmation-emails-to-customers-following-a-store-purchase