Need to pull the wall plate for the switch, and find out if Red or Black comes from the light switch. 14/3 & 12/3 is used for Ceiling fans and bathroom vent with light fans, so that you do not have to pull two romex's. The light switch is not a 3-way, unless you have another switch that also controls the light only on the fan.
The wire that was connected to the fan black should be capped.
The wire that was connected to the fan blue should be connected to the new fixture black.
the whites all connected and green and bares connect.