To attach an Internet Gateway to a VPC using AWS CLI you must know your Internet Gateway ID and Your VPC Id.
To attach you can use the following command:-
C:\Users\priyj_kumar>aws ec2 attach-internet-gateway --internet-gateway-id igw-0185c098195ba1d1a --vpc-id vpc-0aca683c37231c12f
This way you can attach your Internet Gateway to your VPC.
You can verify it using your AWS Console
![](https://www.edureka.co/community/?qa=blob&qa_blobid=18351818199750657099)
Here you can see that your Internet Gateway is attached to your VPC.
Hope it helps