I have spent some time of my summer vacation to write a tutorial named Getting Started, if you are new to Robocode Tank Royale.
In addition, I wrote a tutorial named Beyond the Basics, which any Robocoder should read to advance his/her skills for making more advanced robots. This tutorial is written for the Tank Royale version, but applies the original version of Robocode as well.
Happy Robocoding! ❤️