Explanation
A: To customize your deployment, include a .deployment file in the repository root.
You just need to add a file to the root of your repository with the name .deployment and the content:
[config]
command = YOUR COMMAND TO RUN FOR DEPLOYMENT
this command can be just running a script (batch file) that has all that is required for your deployment, like copying files from the repository to the web root directory for example.
D: In Azure, you can run your functions directly from a deployment package file in your function app. The other option is to deploy your files in the d:\home\site\wwwroot directory of your function app (see A above).
To enable your function app to run from a package, you just add a WEBSITE_RUN_FROM_PACKAGE setting to your function app settings.
Note: The host.json metadata file contains global configuration options that affect all functions for a function app.
References:
https://github.com/projectkudu/kudu/wiki/Custom-Deployment-Script
https://docs.microsoft.com/bs-latn-ba/azure/azure-functions/run-functions-from-deployment-package