Yes, you must use the full account details to do the transfer. Nomad does not have a Pix key.
In the app or system of your Brazilian bank, go to the Pix area and select the option to transfer via agency and account number.
To check your account information, access "Add funds" > "Spending account" or "Investments" > "Deposit."
Just to remind you, you'll need to transfer from an account with the same ownership as the Nomad account.