Insurers don't determine your actual cash value (ACV) settlement based on what you owe, but rather on what the car is worth just prior to the accident. Let's say you owe $20,000 on your new car, but it's only worth about $16,000. If your car is totaled, you might get a settlement check of $16,000 but still owe an additional $4,000 on your loan or lease.
Once you know the approximate value of your car and the cost to carry collision coverage, then you can make an informed decision about purchasing that coverage. Many people find that it's a good idea to cover newer cars, but as cars get older, their values decrease, and you might consider omitting or dropping this coverage to save money on your auto insurance.