Most tutorials for a Shopify Instagram feed without an app stopped working in December 2024, when
The Basic Display API that powered most no-app Instagram feed embeds was removed in December 2024, so tutorials written before then no longer work.
A single public post or Reel can still be embedded with Instagram's official embed code, which needs no API or app.
A live feed now needs the Instagram Graph API through a business or creator account, with a token that has to be refreshed, which in practice means an app or a developer.
For a store, a curated set of imported Reels with product tags usually outperforms a live grid of everything you posted, and it does not break when a token expires.
Not the live, auto-updating grid most tutorials describe. That relied on the Basic Display API, which Instagram removed in December 2024.
The full guide has the formats, the deadlines and the worked examples.