"You can only gain experience for free.
I told this to a restaurateur who had opened his first restaurant. So, in order to help him, I asked to eat in his restaurant for free. Oddly, he said No. 🤔"
Dear Zeid,
I am not part of the Debian project and I'm just an end user.
You can create your own open source projects, projects that are useful for your use cases. Then you can communicate this to open source communities and companies to get financial support (crowdfunding). I will do so. In this way you will experience, but will use your time only to projects that interest you. If your projects will not be appreciated by the community or by the companies, these projects will be still useful for your use cases.
For your first job in a company you don't need certification or talent, just someone (a family member, friend, etc) who suggests your name. In all industries and around the world is so. Furthermore, your first job must be recognized financially otherwise it is called exploitation.