1. Yes you can, it is actually one of the suggested plugins that you can install when you use the Docker Install of Jenkins.
2. By using the Pipeline Editor you can get helpful debugging and visualize stages in a pipeline.
3. The Blue Ocean View is still under active development so any type of Administrative task needs to be done in the classic view.
4. Yes if you click on a node of the pipeline and then click the popdown you will get a detailed view of that particular build stage.
5. No not yet.
6. The stages keyword contains a sequence of one or more stage directives, the stages section is where the bulk of the "work" described by a Pipeline will be located.
7. Yes it does need to be wrapped.