Use an online HEIC to JPG converter
Open the HEIC file in a photo app and export or save as JPG
On iPhone, transfer the photo to a computer and convert it with Photos, Preview, or an image converter
On Mac, open the HEIC file in Preview and export it as JPG
On Windows, install a HEIC codec or use a compatible photo app, then save as JPG
Use a desktop image converter app
Use a batch converter if you need to convert multiple HEIC files at once
Change camera settings on iPhone to save future photos as JPG instead of HEIC