CloudFormation is used as a way to create Amazon Web Services (AWS) resources from template files, such as a JSON or YAML file. In this way, CloudFormation is Infrastructure as Code (IAC).

Since this is just a Getting Started article, let's keep it simple. We'll use CloudFormation to create a Lambda Function named "poc-lambda-function" using the following YAML.

Resources:
  LambdaRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: poc-lambda-role
      AssumeRolePolicyDocument:
        Statement:
          - Action:
              - sts:AssumeRole
            Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
        Version: "2012-10-17"
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AWSLambdaExecute
        - arn:aws:iam::aws:policy/AmazonS3FullAccess
      Path: /

  Function:
    Type: AWS::Lambda::Function
    Properties:
      FunctionName: poc-lambda-function
      Description: my poc-lambda-function
      Runtime: python3.12    
      Code:
        ZipFile: |
          import json

          def lambda_handler(event, context):
              print("Received event: " + json.dumps(event, indent=2))
              return ""
      Handler: poc-lambda-function.py
      MemorySize: 128
      Timeout: 10              
      Role: !GetAtt LambdaRole.Arn

In the AWS Console, let's go to CloudFormation and select Create Stack. Let's go with all of the defaults except we are going to use our YAML file as the template.

Then select Next, Next, Next, Submit. Give it a few moments to deploy, and the deploy should show CREATE_COMPLETE.

And if we go over to the Lambda console, we should see our Lambda Function.

And over at the IAM console, we should see the role.

If you delete the stack, the Lambda Function and IAM Role will be deleted.