How are some people with ADHD able to function exceptionally well vs others who can’t?

I have ADHD and am not medicated. I also have a friend with ADHD that’s also not medicated. But what baffles me is that he’s very high functioning. He does exceptionally well in everything, he focuses well, picks up things very easily, where I struggle to even move sometimes or leave my house. I’m trying to do better, trying to pick up a new skill so that I can leave my terrible job, but it’s been months and I just can’t focus enough. Whereas he’s trying to leave as well but is picking everything much quicker than I am. Is there something wrong with me? Am I not doing enough or am I using my ADHD as an excuse to not do better? I genuinely am trying but I’m so frustrated. Any advice?