1.Where do you set Emails from site features?

Here is the setting to emails from site features, such as contact page, or violation report will be delivered to this address.

2.Where do you set Emails from Automated emails?

we can set the automated emails like subscription or purchase confirmatrion

3. Can we set dynamically smtp from the backend

Admin has an option to  choose and configure  mail gun/Sendgrid settings dynamically now from the backend

4.Can the email templates be edited ?

yes  , they can be edited  and customized at the backend by the site owner

Also the email templates, he can just adjust the variables with content editors