I've had lightroom for a short while now, but I'm completely new to Photoshop. I'm trying to open an image from lightroom as layers in photoshop, but for some reason that option is grayed out/can't be clicked when I hover my mouse over the "edit in" option. Would anyone know why this might be? I have the latest versions of both (on newest version of macOS as of today) and I have tried reinstalling both programs. It could be user error but I'm just not sure, any help would be appreciated, thanks.
You say -
trying to open an image
I assume you have TWO or more images selected in the Lightroom grid.
"Open as Layers" means you need two or more photos selected that will open in the one Photoshop document, with the images appearing on separate layers of the one file.
To open any number of photos (as separate documents) in Photoshop, you would just select one or more files and select "Edit in > Edit in Adobe Photoshop....." ,or [Ctrl+E]