This is a paid asset, but now you can download Basic enter/exit cars Free.
Detail this asset from Unity Store: Original Link
Basic enter/exit cars v1.2 (Latest version)
Basic enter/exit cars is a system that lets your character enter/exit cars. You can walk around and when you are close enough to one of the cars, press a button to enter it.
The system supports multiple cars at the same time and a camera script is included to switch camera between cars and character. Also, if you don’t have a character already, you can use the included low poly character. You can use this in any car game.
– Enter/exit cars using keyboard keys
– Use multiple cars at the same time and automatically enter the closest one
– Smooth camera follow script to follow both character and cars
– Low poly third person character (animated)
– Well commented C# scripts
– Demo scene & car model
– Easy to use
v1.2: First person support