Use the standard bars. Which is 21mm front. Stock rear bar is 13mm or 14mm, or 15mm (rare).
Form your own opinion with some hard driving.
Then try the whiteline bars like you say, if you want.
As a beginner at the track, it's best to start with stock suspension. Race suspension will work too quickly for you and you will be thrown off the track with a sore thumb and busted indicator stalk. But, it only takes 2 track days to learn.