Thankfully, you can quickly export HEIC images from the Photos app. Select all the photos you want to export, then go to File > Export > Export [X] Photo(s). Make sure to use the JPEG format ...

Once the HEIF Image Extensions is set up, you can use these simple steps to convert a HEIC image to JPG using the Microsoft ...

and many more file types. You can also convert a HEIC or HEIF image to PDF format using it. Apart from PDF, you can convert HEIC/ HEIF to JPG, PNG, GIF, BMP, TIFF, and many other formats.