By subdivide, I am referring to when you break up a mesh into even polygons. It sounds like you could be fairly new to 3D modeling and game design since the term subdivide is commonly used. We all need to start somewhere, so I would suggest taking a look at the Static Mesh and FBX pipeline documentation in the link below to familiarize yourself more with best practices and common terms.
FBX Static Mesh Pipeline
We have a wonderful community for all ranges of skill levels and posting questions here as well as on the Forums will get you some helpful answers.
Cheers,