Another nice starter tutorial for CouchDB 2.0
https://blog.couchdb.org/2017/10/10/get-up-to-speed-on-couchdb-2-0-in-45-minutes/
An interesting paid CouchDB course
https://www.udemy.com/understanding-couchdb/
Starter Tutorial for PouchDB
https://techshard.com/2017/09/03/beginners-guide-to-pouchdb/
Some further resources about CouchDB Version 2.0
https://blog.couchdb.org/2016/08/23/check-out-the-road-to-couchdb-2-0-series/