RStudio keeps crashing while trying to initialise rJava library using .jinit command on Mac OS Catalina

Hi, and welcome!

Please see the FAQ: What's a reproducible example (`reprex`) and how do I create one? Using a reprex, complete with representative data will attract quicker and more answers.

In this case, I see the problem, but screenshots are not the best way.

The problem in the error message shows that the Java Virtual Machine didn't load. The reason is given in the jinit{rjava} manual page

Starting with version 0.5 rJava provides a custom class loader that can automatically track classes and native libraries that are provided in R packages. Therefore R packages should NOT use .jinit, but call .jpackage instead. In addition this allows the use of class path modifying function .jaddClassPath.

So, try with .jpackage