create yourself an album in iTunes that only contains the pictures that you want on the iPhone, configure iTunes to only sync albums of your choice, then sync.
The extra pictures will be removed and only those pictures in the album will be left.
OR
Open the Photos app on the iPhone and go to the Moments screen. You should see the word Select at the top right of the screen. Hit it. The word Select will now appear next to each set of Moments. Tap the Select that is next to the group you want to remove and then hit the Trash can icon at the bottom right of the screen.
Follow the instructions and you are done
P
How do I delete photos (8000+)from my Iphone which were mistakenly downloaded from my PC

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