After you have created a gallery page, the next thing would be filling your gallery page with images. Uploading images to your gallery is very simple, just follow the steps below and your gallery page will be ready in no time.
Click on Your Content.
Then go to Pages.
Select the gallery page you wish to add your images to.
Drag and Drop your images or select images from your hard drive. The images will be uploaded one by one in the order you selected them. When the images are uploaded you can reorder, delete and move them to a different gallery. You can also edit image title and description.
Image title is very important in SEO as it is the alt text of your image. To learn more about Alt text, you can go here.