There are people who point out vulnerabilities for others. Hackers. There are also people who test software and IT in general for a living so that other people can use it. This is actually a profession, but currently only certificates prove that you can do it. If you want to know how to become a customer insurer in the IT world and test software and IT, you can ask a long-standing tester at our table about all the resources available, e.g. from the German Testing Board or various communities such as Agile Testing Fellowship, Ministry of Testing or the Software Testing User Group Hamburg, to become a tester.