Add a subdomain for your Shopify-managed domain

If we need change the subdomain of the store there is default functionality

1. From your Shopify admin, go to Settings > Domains.
2. Click Manage for the domain that you want to configure.
3. In the Subdomains section, click Add subdomain.
4. Enter the prefix that you want to add:
   • For international subdomains, enter the two letter country code for your target market. For example, eu for Europe, or ca for Canada.
   • For all other subdomains, enter the text that you want to add as a prefix. For example, blog or shop.
5. Click Add subdomain