From Hyndman, R.J., & Athanasopoulos, G. (2021) Forecasting: principles and practice, 3rd edition, OTexts: Melbourne, Australia located here.
My notes
Chapter 2 Time Series Graphics (html,md)
Chapter 3 Time Series Decomposition (html, md)
Chapter 4 Time Series Features (html, md)
Chapter 5 The forecasters toolbox Part 1 (html, md)
Chapter 5 The forecasters toolbox Part 2 {html, md)
Chapter 7 Time series regression models {html, md)
Chapter 8 Exponential smoothing {html, md)