Instagram Basic Display API in PHP
You can go through the Documentation available at https://developers.facebook.com/docs/instagram-basic-display-api/getting-started, but I recommend watching this video instead: https://www.youtube.com/watch?v=X2ndbJAnQKM.
Check https://developers.facebook.com/docs/instagram-basic-display-api/guides/getting-profiles-and-media and https://developers.facebook.com/docs/instagram-basic-display-api/reference/media.
Many repositories have code for the Legacy Instagram API, which was disabled on June 29, 2020. That will not work anymore, and you must use the Basic Display API or Graph API. The latter targets Businesses and Creators and gives insight and full control over those accounts.