The HSA deduction is a deduction that you can claim for any post-tax personal funds that were applied to your HSA. If your HSA contributions were done entirely through your employer (whether or not it was matched by your employer in anyway) and was pre-tax, you will not see an amount in that line. Because the funds that you contributed directly through your employer's payroll are already not being taxed, you will not be able to take another deduction for the amount (basically, no double dipping).
The HSA deduction is a deduction that you can claim for any post-tax personal funds that were applied to your HSA. If your HSA contributions were done entirely through your employer (whether or not it was matched by your employer in anyway) and was pre-tax, you will not see an amount in that line. Because the funds that you contributed directly through your employer's payroll are already not being taxed, you will not be able to take another deduction for the amount (basically, no double dipping).
I cannot see an input on turbotax for employee contribution
That's because the is no such thing as "employee" contribution.
All contributions shown on the employee W2 are "employer" contribution because the employer made the deposit for the employee.
No My employer contributes 1600$ a year and my contribution is 900$ a year to meet 2500$ deductible line 25 on a 1040 can not find input on turbo tax
If those contributions are pretax, they don't belong on line 25. Usually all contributions made through your employer are pretax. That means your deduction was made to your wages on the W2, not on the tax return.
the employer contribution is pre tax I wrote a personal check for 900$ to get to 2500$ after 2500$ the company picked up 100% of medical costs
Then only your $900 after tax amount belongs on F1040, line 25. The employer $1600 was not included as a taxable wage to you (W2).
Find the HSA section (medical deductions and credits) and look for the screen "Enter Your HSA Contributions". Look for the employer $1600 on the top line. Add your $900 to the line "All Other Contributions".