Welcome to Android Central! Use any file manager app (like
Total Commander) to copy the photos to the SD card. Photos taken by your camera will be in the /DCIM/Camera directory on internal storage. I always recommend the Copy command rather than Move, because Copy doesn't delete the original file. This is important in case something goes wrong with the file transfer. Once you're sure the files copied correctly, then you can delete the originals.
It's probably easier to connect the phone to your computer via USB, swipe down the notification panel, tap the USB icon, and make sure MTP is selected. Then open Windows Explorer on your computer and select the phone. You can now drag and drop files, and you should be able to see the microSD card as well in this display. While you're at it, I strongly recommend you back up your photos to the computer hard drive (or take advantage of
Google Photos Auto Backup), since it's risky to have your photos saved only to your phone or an SD card, due to the possibility of loss, damage, or file corruption.