You're mixing two different things:
VPN as a tunnel provider versus SSL/TLS for application-specific encryption
IPsec over TLS/DTLS for other reasons
The main point for a VPN is to create a tunneled link where you can pass private traffic in a secure way and with private addressing. A VPN can be used with any type of traffic, without specific setup on the ...
They both provide authentication and confidentiality. The difference is TLS is configured by the application. In other words your application needs to be configured to use it.
An IPSec VPN, on the other hand, is configured at the network layer and creates a tunnel for the application. The application is unaware that a VPN is being used.