Thank you for reaching out and posting this question!
The Shopify system will automatically send out an order confirmation email when customers complete their purchases. If this is the email that you're referring to, then you can edit the notification templates directly through the settings ('Settings > Notifications') of your admin. Or, if you're referring to orders from Shopify POS, then you can manage receipts to reprint receipts or resend the via email.
I noticed that you're a new member of our Shopify Community! I'd love to hear more about your business and share some resources to help you get started. What kinds of products are you selling? Do you have a marketing plan prepared for your store?
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