Let syntax error

I am new to processing and java and was trying to use let but when I compile it says syntax error. Do I have to add a plugin for that and how do I do it?

Processing is it’s own language, with it’s own syntax. Unlike pure JavaScript, it doesn’t use “let” as a key word.

In fact, Processing is a typed language, meaning that variables can only be assigned an object of the right kind.

Try one of these keywords instead: https://processing.org/reference/#data