Use WAVLAB or just Cubase “mastering section” to master?

Seems like they are about the same.

I have Cubase & have access to Wavelab.

For someone new to mastering, is there an important difference between?

I have 3 songs (all to be on the same demo CD).

ADD-ON QUESTION -

I feel stupid asking this but...how do I get started with mastering this way?

MEANING: Do I mix/export my Cubase songs to a 2 track Wav file & then reintroduce that file into Wavelab?

Or, is there more of an INTERNAL way to AUTOMATICALLY transfer all my tracks into a 2-track stereo container & then import into into Wavelab?