Welcome to Android Central! Open your App Drawer and look for the Samsung folder. My Files might be there. As far as I know, all Samsung devices (at least all recent ones) include the My Files file manager.
For any file manager, though, the process of copying files is about the same. Find the photo you want to move (usually in the /DCIM/Camera directory of Internal Storage), then long-press it to activate a multi-select mode. Now check which photos you want to copy, and then tap the Copy option (or tap the Menu button and then Copy). Use Copy, not Move, in case something goes wrong with the file transfer (Copy preserves the original file, while Move deletes it). After you select Copy, it'll ask you for a target directory--select the microSD card, and the directory where you want the files to go to.
It's generally easier to connect the phone to your computer via USB and use Windows Explorer to drag and drop the files.
01-17-2016 11:41 PM