Composition Settings grayed out

Hi, I imported this photoshopped picture (322x406) I imported into After effects and Im trying to match it to 1920x1080 of my video because its not motion tracking accurately when I use mocha. Problem is, when I right click the click the photo, "composition settings" is grayed out. It seems I need to use the recompose feature, but after watching about 15 youtube videos I still dont quite get how to use the precompose for the picture, as it seems to create a new layer. Im quite new to this, any help would be greatly appreciated! TIA
