Internet does not come on Nat.
Did you mean NAT server has no internet access or internal client has no internet access? Please clarify more details.
For internal clients, the Default Gateway should set to NAT server's internal IP address.
To test that your Network Address Translation (NAT) Service in Windows Server is working, please refer to the following steps:
1.Logon to a Windows machine that is connected to the internal network. Run IPconfig /all to confirm the IP information of this windows computer.
2.The IPv4 address of the client should be in the internal network.
3.The Default Gateway should set to NAT server's internal IP address.
The following article talking about how to configure NAT step by step, you could have a look:
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
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