Create multiple yml files in Azure pipeline

If you want to have multiple pipeline yml files other than the single default one (with name: azure-pipelines.yml):

Step 1:
Click "pipeline" menu in Azure DevOps, and create a new pipeline yml file. You can rename the yml file with a meanful name, after modify the content, create Save button on the top-right, normally you will choose create a new branch to hold your new created yml file. If this yml is not the default one to be triggered by "- master", you can set

trigger:

- none

Step 2:
Run the pipeline to see if it works as your expectation. If it is, you can merge the yml file into "master" branch

Step 3: You can manually run the new created pipeline yml file as per needs.

Normally we only have one yml file with trigger "- master", the other yml files can be triggered manually or per scheduled. As the yml file will be merged into master branch, so it can be ran in master branch, and any branches from master afterwards.