I found the Rubocop yml file

Is this the file I need to edit in order to change offences that I don’t agree with or want ?

So, for example, If I want to mute these offences, is this file the place to do it ?

Read the first paragraph

no, you would not modify rubocop itself
create a file wherever you want it after considering how rubocop looks for them, and then put whatever overrides in that file