It's easy to steal cars in Cyberpunk 2077, as you just need to hop into the seat and drive away, with no convoluted hotwiring minigames or anything else to deal with. However, your 'ownership' of these vehicles is only temporary, as there's no way to save them or otherwise claim them as your own. While you can happily cruise around Night City in your stolen ride for as long as you like, you can't add it to your garage so you can return to it again at a later time. If you exit the vehicle and walk too far away, or fast travel to a different location in Cyberpunk 2077, then the car is gone for good and you'll need to start looking for a fresh set of wheels.
The main way to get new cars and bikes to add to your garage is to buy them when someone contacts you with news of a new vehicle up for sale. Find them on the map and pay them a visit, fork over the eddies and you'll have yourself a new ride.
There are also some vehicles you can get by completing missions, so if you don't want to spend your hard-earned cash on a car, complete some more side missions. Some of the cars you can earn are great, too, so just play the game for of the best options. Cars in Cyberpunk 2077 don't have massively different stats though, so most vehicles will basically do the job you need them for - all you're really changing are the looks.
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