If you try out open source software that interests you, and after reading the documentation you don't understand how something works or have an idea of how the

If you try out open source software that interests you, and after reading the documentation you don't understand how something works or have an idea of how the program could be better, give specific feedback by (for example) raising an issue at GitHub. I am a Fortran programmer primarily, and most Fortran compilers are written in C. When I encounter bugs I report them at the Intel Fortran forum, GitLab (for LFortran) and bugzilla (for gfortran). So you can contribute to a project written in X without knowing X.