Reapplying for F2 visa. Need some inputs

I had went for My F2 visa interview recently at the Chennai consulate. I had mine rejected under 214(b). I did not get any reason though.
The questions were mostly on how my husband can support while he is on his PhD and also about where we met and when we met.

I previously had been to the US with B1 and we met in the US. I told him the same. He didn’t ask for any amrriage certificate per se.
I did show the I-20 for F2 and then my Visa was rejected.

I am planning to re apply again since going on F2 seems better than going on B2 and doing a COS. I am planning to reapply after month. I was also thinking it going on B2 might be a better way since I also risk the next time of getting the Visa.
What can be the waiting time for re application… can I reapply in 15 days but schedule the appointment one month later ? Or do the appointment itself after a month ?

Should I have to do biometrics again ?