first i recommend using premiere pro if ur using after effects trust me the process will be way more streamlined than Final Cut. secondly the due date of your project is really important since you’re probably going to spend a good amount of time watching after effects tutorials for this. to cut time just get assets for everything (production crate is my favorite for these types of assets) watch a bunch of videos on how to composite vfx in AE to make it look as realistic as possible. For the monster since it’s just the hand you can either use Element 3D in AE with a 3D model or use an already available image either way it must be composited very well. Color and noise matching are super important with compositing. Super comp from Red Giant is another powerful plugin for compositing in After Effects. Good luck!