If your domain name was registered through a 3rd-party domain registrar, you need to accomplish two things to successfully link your domain to your Shopify store.
Add Shopify’s Resource records in the domain’s DNS.
If you have more than one Google account in browser session, you will be prompted to select your Google account. Select the owner account of your domain.
Click Accept if Shopify asks permission to view your Google account information.
Enter your Shopify store name when being prompted, and click Connect this store to Google Domains to continue.
Log in with your Shopify account.
The email address and password at this step is not the same as your Google Domains account. Use your existing Shopify account to log in.
Click Accept if Shopify asks permission to manage your Google domain resource records.
From the Shopify console, go to Online Store | Domains page and review the primary domains setting. If your domain is not selected by default, pick your domain name from the Primary domain drop down list, check “Redirect all traffic to this domain”, then click Save.
Test your domain address in a browser. If the domain URL loads successfully, Congratulations! You’ve successfully connected your domain.
2.) Add Custom Domain in Shopify
Once you’re done adding the DNS records, you may now add your domain name to your Shopify account.
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