The "Back to Basics" videos from cppcon are pretty good, IMO.

For lambdas: Back to Basics: Lambdas - Nicolai Josuttis - CppCon 2021

https://www.youtube.com/watch?v=IgNUBw3vcO4

Back To Basics: Lambda Expressions - Barbara Geller & Ansel Sermersheim - CppCon 2020

https://www.youtube.com/watch?v=ZIPNFcw6V9o

For auto, this one is short and summarizes some of the gotachs:

C++ Weekly - Ep 287 - Understanding `auto`

https://www.youtube.com/watch?v=tn69TCMdYbQ