wow, i've never even heard of "Add divisions"...
ajmooch is right, just use cut face, split polygon, or inserte edge loop, whichever tickles your fancy better
if you haven't altered any verticies or added edges since the creation of the cube you can up the subdivisions used in the cube in it's history nodes in the channel box
that's a "Ch" pronounced as a "K"
Computer skills I should have:
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