Thank you for getting in touch. If you're looking for general information on setting up your GST in India when using Shopify, we have a comprehensive FAQs page on this topic I would recommend. In terms of GST invoices, there are some apps you can install and use to create them—I would recommend checking out Order Invoice GST and Advanced GST 2.0.
If you have any other questions about GST and taxes in Shopify, please let me know.
Victor | Shopify Social Care
You will get the GST Input based on the purchase invoices of your vendors. You are required to summarize all purchase invoices of the vendors and claim the GST Input Tax Credit when you will file your GSTR 3B Return.
Please let me know if you have any other query.