How can I replace KMS resources element ARN with variable

Does anyone know how I can have the resource section of my policy ARN as variable?I don’t want to use wild card *,I only want to grant access to a specific KMS key that was created.Please I welcome suggestion on how to get this done just like how I did for the s3 ARN

statement {
actions = ["kms:Decrypt", "kms:GenerateDataKey","kms:DescribeKey" ]
effect = "Allow"
resources = [
 "arn:aws:kms:us-east-1:123456789102:key/04b34581-52df-4f0e-5c9g-12322bd11909d"]

 statement {
actions = ["s3:ListBucket"]
resources = [
  "arn:aws:s3:::${var.bucket_name}"
]
effect = "Allow"