Hello is it possible to enter chords in BIAB VST via MIDI keyboard? or is it possible to import a MIDI file which contains chord data?

You can use the Chord Picker Tool below in the link to add chord easily to the vst.
You would have to import the midi chord file to Biab/RealBand then save as SGU then open in the Plugin.

I was looking at Midi Chord input the Chord Picker Tool.