Turbotax is asking to enter personal HSA contributions to HSA indicating box 12 ... but box 12 in w2 has a bunch of different number from 12dd, w, c and d Which one is it?!

Health Savings Account contributions through payroll deductions are reported on your W-2 in box 12 with code W.  

This amount will automatically transfer to the HSA section of your tax return and you should see it on the screen as you go through that section.  If you made any additional contributions to the HSA outside of your payroll contributions, those should be entered on their own as you go through the HSA section of your return.

Don’t enter payroll contributions later in the program. They are only collected from your W-2. Later in the program, you only enter extra contributions that you might have made out of pocket and not through payroll.