You can record to multiple software instrument tracks simultaneously.
When Enable Complete Features is selected in Logic Pro > Settings > Advanced, you can also record to multiple software instrument tracks successively (in Cycle mode).
In Logic Pro, click the Record Enable button 
in the track header of each track you want to record to. Each clicked Record Enable button turns red to indicate that the track is ready for recording.
Move the playhead to the point in the ruler where you want to start recording.
Set the metronome for recording, if desired.
Click the Record button 
in the control bar (or press R) to start recording.
Use your MIDI keyboard, Musical Typing window, or onscreen music keyboard to record a part.
A new MIDI region appears on each of the record-enabled tracks.
Click the Stop button 
in the control bar (or press the Space bar) to stop recording.
In Logic Pro:
To continue playing previous tracks while recording, do one of the following:
Choose Record > Overlapping MIDI Recordings > Cycle Mode On > Create Tracks.
Choose File > Project Settings > Recording, then choose Cycle > Create Tracks from the Overlapping MIDI Recordings pop-up menu.
Control-click the Record button in the control bar, choose Recording Settings from the shortcut menu, then choose Cycle > Create Tracks from the Overlapping MIDI Recordings pop-up menu.
To mute all previous tracks while recording, do one of the following:
Choose Record > Overlapping MIDI Recordings > Cycle Mode On > Create Tracks and Mute.
Choose File > Project Settings > Recording, then choose Cycle > Create Tracks and Mute from the Overlapping MIDI Recordings pop-up menu.
Control-click the Record button in the control bar, choose Recording Settings from the shortcut menu, then choose Cycle > Create Tracks and Mute from the Overlapping MIDI Recordings pop-up menu.