I would like to clarify the context for the question: I have studied different types of exploiting but all the studies I have carried out were with command line programs and with functions that I already knew beforehand. It is taking me a lot of effort to find on the internet how to analyze a normal application and look for vulnerabilities. If anyone knows any methodology, any video where it explains and shows or some information on how to perform a reverse engineering and analysis of a desktop application to find bugs, I would greatly appreciate it. Since all the examples I find are from binaries and I have also tried looking in exploit-db but there is like seeing the solution of the problem without seeing the analysis. I would like to learn how to perform a black box analysis on a modern desktop application today.
I am not an expert, but have you hear about fuzzing??
"Fuzz testing or Fuzzing is a Black Box software testing technique, which basically consists in finding implementation bugs using malformed/semi-malformed data injection in an automated fashion." [link]:https://owasp.org/www-community/Fuzzing