No don’t enter the loan expenses, they’ll be taken care of automatically.
What happens in the TM is when you take out a loan in the future, is that the amount of the loan is put in your Wallet, and the Loan gets a balance that starts accumulating interest and payments are made (from your Wallet). For an amortizing loan the amortization schedule is used and recalculated anytime there is a pre-payment (which can happen with Deposit Priorities kicking in). Normally for a car loan, you would enter an EXPENSE for the car as a one time (same start and end date) expense on the same day the loan is taken out. That expense will be taken out of your Wallet, so should be mostly covered by the loan taken out, unless your cost is higher due to a downpayment. The loan is not actually linked to the car, it’s just a personal loan, but you do need to enter the car expense. This is the way it works for all LOANS in the TM started in the future. You go to the bank/dealer, get a cheque for the loan, then spend the cheque.