I need to use the 'trim path' operation, but I can't find/view the 'Add menu' in either my comp or timeline panel. I'm still pretty new to AE (cc) so I apologize if this is a dumb question. Thanks in advance!
You need to create a shape layer by either using the drawing tools or from the Layers menu. Trim Paths is specific to shape layers.
Right I indeed had a shape layer, but I made another one just for fun and Add has returned! Thank you!