Further Reading
There are many books that are published for users that are new to the Linux operating system. Here are a few of my personal favorites.
Working with Linux - Quick Hacks for the Command Line (ISBN 978-1787129184) by Petru IÅŸfan and Bogdan Vaida is a strange collection of nice tips and tricks, and sometimes that is all you need.
If you are able to read German, all the books by Michael Kofler (https://kofler.info) should be on your bookshelf, even if you are an experienced Linux user!
The Microsoft website hosts very good documentation on regular expressions: https://docs.microsoft.com/en-us/dotnet/standard/base-types/regular-expressions. And I do like http://regexone.com if you want to practice using regular expressions.
The awk
utility comes with a big manual (https://www.gnu.org/software/gawk/manual/gawk.html), but it's maybe not the best place to start. Shiwang Kalkhanda did a very good job in Learning AWK Programming (ISBN 978-1788391030), producing...