NodeTool@1 isn't used in this manner. It's responsible for finding and pulling a specific version of Node; which is probably why you're getting the error you're getting.
To configure your app setting environment variables from your group, you need to set the appSettings
property of the AzureWebApp@1 task.
- task: AzureWebApp@1
inputs:
# app settings is a string of -key value
appSettings: -AUTH_MICROSOFT_ENTRA_ID_CLIENT_ID $(AUTH_MICROSOFT_ENTRA_ID_CLIENT_ID) -GRC_MAPPER_URL $(GRC_MAPPER_URL) -GRANT_TYPE=$(GRANT_TYPE) -BASE_URL_TOKEN $(BASE_URL_TOKEN)