yes you need to enter the traditional IRA contribution. think of the backdoor Roth as 2 separate transactions, a non-deductible contribution (in Deductions & Credits section) and then the IRA conversion (under Wages & Income) and they get linked together on Form 8606, but you need to be careful to answer all the questions in both sections.
Then check the outcome on Form 8606 and you should be seeing $0 on Line 4b of your 1040 assuming no other taxable distributions (assuming the conversion exactly matched the contribution, sometimes there is a delay in the conversion and little bit of earnings get taxed).
Here are the instructions from Turbotax on this:
https://ttlc.intuit.com/turbotax-support/en-us/help-article/retirement-benefits/enter-backdoor-roth-...
