I will be explaining how to automate adding a task to a certain bucket in planner with power automate

High view look at the flow:

The first part List buckets is pretty simply you need to select the group Id and plan Id you are wanting to focus on. If you open planner and click the plan you want to focus on look in the address bar and you can find what you need for this part. In my case It found the names so I selected them in the drop down menu

Next create a step called Initialize variable Bucket ID like so:

I then created a Compose action because I wanted to get the bucket id when this name was matched. If you don’t need a variable for that then you can skip this step

Now create an apply to each item and in the box for select an output from previous steps enter the dynamic content for Value (from List buckets above)

Then create a new condition where on the left is Value Name (from List buckets above) is equal to Outputs (From the compose action above)

If you skipped the compose action then instead you will put the name of the bucket there instead of Outputs.

example: To Do

On the if yes side add a set variable step and select BucketID and then for the value enter value ID (from List buckets above)

Finally we will then add an action called Create Task

On the Bucket Id line enter the variable BucketID

References:

https://powerusers.microsoft.com/t5/Building-Flows/On-bucket-creation-quot-Schema-validation-has-failed-Validation/td-p/182570
https://powerusers.microsoft.com/t5/Building-Flows/Getting-bucket-Name/td-p/171129