Getting error in creating aws lambda for screen shots

I have created the s3 bucket and the cf and updated the yaml file with my settings. But when try to create the lambda function with the cloud formation. I am getting the below error:

“Template validation error: Invalid template property or properties [functions, provider, service, plugins, custom, resources]”

I take the reference from this URL but not able to figure it out

Can you please check it for me and help in getting this done?