When you create a customer profile on Shopify it does not automatically create an account for them.
If you'd like for them to create a customer account for your Shopify store, you can send them an invite.
From the Shopify Dashboard ➡ Customers
From their customer profile, click the button Send Account Invite
Create a message they will read and click Send Email
When they receive the email, they can click on Activate Account
Then they will need to create a password & click Activate Account again
PRO TIP: You can send emails to all your customers in bulk like this.
Please note Shopify customer accounts are optional for Ongoing Subscriptions.
This tutorial is just in case you require customer accounts and are in need of figuring out how to send a customer a customer account invite via Shopify, after creating their customer profile.