Mega backdoor Roth contribution

My income is higher than the Roth IRA limit so I cannot contribute to Roth IRA directly. My employer offers 401K plan and it also have an option for in-plan conversion so I can contribute after tax money from my monthly paycheck to my 401K account in addition to my normal 401k contribution. I'm trying to fill out the Traditional and Roth IRA deduction portion in TurboxTax and I don't quite know if my situation counts as Roth IRA.

For this type of mega backdoor Roth approach in the same 401K account, does it considered as a Roth IRA account?

Is my 401K account with in-plan conversion considered a Roth IRA account? Do I have to report these contribution as Roth IRA contributions? I received a 1099-R for the contribution and it shows up in my W-2 box 14 as Other and AFTAX.