I have been where you are now and I have felt what you're feeling - like you're stuck in a never-ending and overwhelming struggle, scared to choose the wrong purpose, feeling like it's always out of your reach and that you're failing at it completely.
I did what you have done - read the blog articles, watched the YouTube videos and Googled many many times "How do I find my purpose?". But all of that just seemed to keep me stuck and lost. Until one day I looked at things a little differently and I asked myself a question that completely opened up my eyes, my mind and my heart.
Now I'm not saying that I never had another struggle, fear or frustration after that. But I never felt lost again. I knew exactly which mountain I was here to climb - and that is, sometimes, the biggest battle of all.