Steps to create a new NextGEN Gallery and add photos to that gallery:
Go to Gallery > Add Gallery/Images.
Name your new gallery and click “Add Files”. Navigate to the folder that contains your gallery images, select them and click Open. Click “Start Upload”.
After the the upload is complete, navigate to Gallery > Manage Galleries.
Click on the new gallery name. If needed, add a descriptive title for each image and add alternative text. Alt text is used by search engine bots and vision impaired visitors.
Click “Save Changes” – you have a new gallery containing images!