If you don’t have AWS VPN installed go here (go here to download updated version if you receive an error in connecting to VPN):

https://aws.amazon.com/vpn/client-vpn-download/

Download the AWS Client VPN for macOS, 64-bit

To connect using the AWS provided client for macOS

1. Open the AWS VPN Client app.
2. Choose File, Manage Profiles.
3. Choose Add Profile.
4. For Display Name, enter a name for the profile.
5. For VPN Configuration File, browse to the configuration file that you received from your Client VPN administrator. Choose Open.
6. Choose Add Profile.
7. In the AWS VPN Client window, ensure that your profile is selected and then choose Connect. If the Client VPN endpoint has been configured to use credential-based authentication, you'll be prompted to enter a user name and password.
8. To view statistics for your connection, choose Connection, Show Details.
9. To disconnect, in the AWS VPN Client window, choose Disconnect. Alternatively, choose the client icon on the menu bar, and then choose Disconnect <your-profile-name>.