Blueprint Boolean operations on existing static mesh

I’m trying to create a project where a pre-made static mesh (right now I’m just working with a cube for simplicity) can be converted to a dynamic mesh and have boolean operations un on it - right now just subtracting cubes from the cube, basically. The tutorials I’ve found seem to mainly have the dynamic mesh being generated inside the construction script with something like Append Box, as opposed to an already existing static mesh pulled from my project. I think I’m not converting it correctly, but I’m not sure how to fix it - any help would be much appreciated!