Are you looking to wire the L298N directly or use a module like
Being a 3.3v device you may need a logic level converter.
Personally I would get it working an arduino first then translate the working system to Microbits (only because I have more experience with Arduino and have not played with Microbits at all).
If you are looking at using a L298N module then the wiring is straight forward and feedback protection is incorperated into the module. Here is a good tutorial on L298N and H-Bridge drivers in general.
As you are only sending signal to the L298N module and not recieving signal from it the 3.3v signal level from the MicroBit should suffice.
Hope this helps.