Urgent help! F1 transfer back to H1B

I have H1B before and used up almost three years. But about six years ago, I transfer to F1 for a PhD degree. Now a company gave me offer. Could I transfer back to H1b and not to apply for new H1 again? What should I submit for the transfer? What if I use OPT and during the OPT time, starting to apply for green card? Thanks!!