How to identify store is online 2.0 or later ?

[jaydip_patel]

currently developing public Shopify app for our valued client that has widget icon at storefront to give discount code. Currently we are using theme app extension "App Embed blocks" that support Online 2.0 stores, but what we need to do for old stores? how do we check and implement solution for old store and 2.0 store together ?For old store do we need to use script tag or asset API ? How do we get that store is online 2.0 or old store?