It is simple to create an Internet Gateway. All you need to do is configure your AWS and use the following command:-
C:\Users\priyj_kumar>aws ec2 create-internet-gateway
This command will give you an output stating your Internet gateway ID.
{
"InternetGateway": {
"Attachments": [],
"InternetGatewayId": "igw-0185c098195ba1d1a",
"Tags": []
}
}
Hope it helps.