Long-press an image in your browser or email and tap "Download image" or the download icon . Photos will usually be saved directly to your phone's gallery or "Downloads" folder. How to Upload JPG Files
Go to iCloud Photos , select your images, and click the download icon . Download upload jpg
If your file is in a different format (like PNG or HEIC) and you need a JPG: Upload and download photos on iCloud.com - Apple Support Long-press an image in your browser or email
Visit iCloud Photos, click the upload icon (cloud with an up arrow), and select the files from your computer. select your images
Go to Google Drive , click "+ New" at the top left, and select "File upload" to choose your JPG.