Seems like some people still have trouble uploading photos into their post so here’s a quick guide.

Click the plus sign (highlighted in yellow).
After clicking the plus sign, a pop up menu (highlighted in yellow) will appear. In the search bar of that pop up menu, type “image.”
Searching for image will show these options. Highlighted in yellow are options to add pictures. “IMAGE” only posts ONE picture. “GALLERY” posts MULTIPLE pictures in a “gallery.” Most of the pictures in this post used the “IMAGE” option.
After clicking either the IMAGE or GALLERY option, OpenLab will give you the option to upload your photos (highlighted in yellow).
Clicking the “upload button will show another pop up menu. Select the option where you can find your pictures.

Then your pictures should appear in your post.

OpenLab gives you the ability to write captions for your photos; just click on the image and you’ll see “write caption.”

Extra: below would be all the images from above compiled into a “gallery” if you chose the “GALLERY” option: