You can copy an AMI to another region using the AWS Management Console, AWS CLI, or SDKs.
Example (AWS CLI):
aws ec2 copy-image --source-image-id ami-0abcdef1234567890 --source-region us-west-2 --region us-east-1 --name "My copied AMI"
This command copies the AMI with the ID ami-0abcdef1234567890 from the us-west-2 region to the us-east-1 region and names the copied AMI "My copied AMI".