Hello kereta7,I understand that you want to clear up some space on your iPhone by deleting some photos. Let's go over how to do this to get you more space. The first thing is to import the photos to your computer. To do that, Take a look at the first article below to walk you through this on either a Mac or a PC.
Import photos and videos from your iPhone, iPad, or iPod touch to your computersupport.apple.com/en-us/HT2...Once you have your photos imported, you can then go through the steps of deleting them. Take a look at the information below to delete a photo one at a time or delete multiple ones. If yo are on iOS 9, you will also need to delete them in the recently deleted folder to completely remove them.
Organize photos and videoshelp.apple.com/iphone/9/#/i... care