How to sort gallery galaxy s8

[John49]

How do I put photos from gallery on to sdcard 

And do they still stay in gallery when I have moved them

[BandOfBrothers]

When you first insert a Sd card in the phone it'll ask if you'd like the photos to go to the Sd card as default. 

Or launch the Camera App and hit the cog ie settings and you can change the default place there @John49

Yes even tho the photo itself is in the Sd card it'll remain in the Gallery to view. 

[John49]

Thank you bandofbrothers most helpful answer