It is generally possible to drive a friend's car without having your own car insurance, as long as you have the owner's permission. The owner's insurance policy will typically be the primary payer for any damages caused by the vehicle, and the driver's own insurance may be secondary and cover personal injury or medical expenses. However, it's important to note that there may be exceptions to this rule, such as if the driver lives at the owner's house full-time or frequently drives the vehicle. In these cases, the driver may need to be listed on the owner's policy in order to drive the car.
It's also worth considering non-owner car insurance, which can provide coverage for drivers who frequently drive someone else's car. This type of insurance can be useful for people who frequently borrow cars or drive cars that are not their own. Additionally, it's important to note that unauthorized use of a car can be seen as theft or unauthorized use of property, which is illegal in many jurisdictions. Therefore, it's crucial to ask for explicit permission from the owner before driving their car, and to ensure that the owner understands the potential risks involved.