@michmoor no to "commit confirm" of a candidate config. In TNSR CLI when you type exit you commit your change. Please test your changes in a lab environment before running them on production.
Please read the article there is an answer to almost all your questions.
"| match" instead of "| grep". You can match using regex.
matching parameters is case-sensitive.
regarding the "section" you can do something like this:
show run bgpto display BGP configuration.
