Hi@akhtar,
You can use aws_s3_bucket_object resource to create one folder in s3. I have attached one example below.
resource "aws_s3_bucket_object" "folder1" {
    bucket = "aws_s3_bucket"
    acl    = "public"
    key    = "Folder1/"
    source = "/dev/null"
}
I hope this will help.