Hello petek121,
If you are wanting to get all your photos from your iPhone to your PC or Mac, than we would suggest looking into using iCloud Photos: Set up and use iCloud Photos - Apple Support. iCloud Photos will allow you to see all your photos anyplace you are signed in with your Apple ID.
If you want to export the photos from your computer, these steps from Export photos, videos, slideshows, and memories from Photos on Mac - Apple Support should help:
"Export photos in a selected format
You can export photos so that you can import them and work with them in other apps. The easiest way to export photos is to drag them to a location in the Finder. You can also use the Export command, which allows you to specify file format, filename, and subfolder organization settings. You can choose the size and format for the exported photos. You can also export a Live Photo as a still image.In the Photos app on your Mac, select the item you want to export.Choose File > Export > Export [number] Photos.Click the Photo Kind pop-up menu and choose the file type for the exported photos.JPEG creates small files suitable for use with websites and other photo apps. TIFF is a lossless file format that works well for transferring photos between computers and apps.PNG is another lossless file format popular for web images.To specify the size, quality, and other export options for a specific file type, click the down arrow beside the Photo Kind pop-menu, then select the options you want: JPEG Quality pop-up menu (JPEG files only): Choose a resolution (the number of pixels in the exported image), which affects display and printing quality. 16 Bit checkbox (TIFF files only): Select to export an image compatible with older 16-bit computer devices.Color Profile pop-up menu: Choose a color profile to maintain similar display or printing quality on monitors or printers different from your devices.Size pop-up menu: Choose the size of the exported image.Click the File Name pop-up menu and choose how to name the exported files (this step is optional).You can name your exported files using the titles you’ve given them in Photos, their filenames, or a filename numbered sequentially. If you choose Sequential, you can specify text to appear before each number (for example, Birthday - 1, Birthday - 2, and so on). Click the Subfolder Format pop-up menu and choose how to divide the exported files into folders.For example, if you export photos from several different days, you can have Photos export each day as a subfolder named after the day. Choose None to export the photos as individual files without subfolders.Click Export.Choose where to save the exported photo files, then click Export."
Have a good day.