Yes, hreflang tags are added automatically to your store pages the moment you publish your translation language and assign it to a market.
Note that the hreflang tags are managed by Shopify and are generated based on your Shopify Market settings. Our langify app does not have a direct influence on them.
You can double-check your hreflang tags with any SEO tool, such as technicalseo.com.
This is an example of how the hreflang tag scan should look:
