U can go through the article entitled “Introduction to RNA-seq data analysis” by Myrto Kostadima. Its well conceptualized, concise and contains all commands for performing data analysis.
You could check out the book "RNA-seq Data Analysis - a practical approach" (https://www.crcpress.com/RNA-seq-Data-Analysis-A-Practical-Approach/Korpelainen-Tuimala-Somervuo-Huss-Wong/p/book/9781466595002)
It starts from scratch and gives you a general introduction into the topic, but also provides hands-on with code examples of the tools to use.