The question asking about contributions to my HSA, it asks me for the amount listed in box 12. I have 4 different categories in 12 ie C,E, W, DD

Code W is your HSA contributions.  Those get entered when you enter your W-2. 

I think you use all of them

Don't use all of them; only code W is for HSA contributions.  @JBB1

 

C: Taxable cost of group-term life insurance over $50,000

 

DD: Cost of employer-sponsored health coverage. More info

 

E: Contributions to your 403(b) plan

 

W: Company contributions (including employee contributions through a cafeteria plan) to an employee's health savings account (HSA)

 Box 12 is used to report several different important items to the IRS. Each item has its separate code number. Because there are so many different codes that can be reported in box 12, most W-2s will have several separate box 12s, a, b, c, d.  Enter each one separately with its correct code number. Don’t combine them.