part of a business want to make it house?

Zoning laws are local. Then there may be other codes that are state, county or municipal, such as building, health, fire, which may each determine the necessary features you will need to incorporate into the proposed design.

A couple here recently bought an old church and converted to single-family residence without any permission at all.  Completely legal, once they had the engineered septic system installed and inspected.  The only "fire code" was that they were required to install hardwired smoke alarms in each sleeping area and a CO alarm "on each level", which cost them a total of about $200.

The entire town is zoned "residential or agricultural" and anything else is granted by special exception or variance.  Converting to residential needed no zoning change or building permits whatsoever.

You have to check zoning laws. In order to split it like that it has to be zoned for both residential & commercial. Zoning laws are local & you have failed to provide a location. 

The property needs to be rezoned for commercial AND residential.

I hope your business won't need a literate manager, because you have failed at that.

Housing zoning is a MUNICIPAL area of law, so since you chose NOT to tell us what city you're in, no one here can guess at what you need to do.

Be sure it's ok with the zoning.

i would ask a lawyer about it