Popup newsletter

In the theme editor (Customize) => Section, click Popup newsletter

4 Style

Popup Split, Left Image

Popup Split, Right Image

Popup Box

Popup Top Image

You can settings

• Enable/Disable

• Layout Style

• Width, Height

• Time, and Cookies

• Background

• Color

• Image

• Text content

Email subscriber list management

https://help.shopify.com/en/manual/promoting-marketing/create-marketing/shopify-email/email-subscriber-list-management