I feel like whenever I play ADC, my teammates always inevitably feed. And no, it's not me. I have no control over how the rest of my team plays, but they always wind up being terrible.
But saying "I don't know those roles well enough" means, learn those roles! Expand your knowledge. You're the only person that will be in 100% of your games. So, learn and absorb more information and learn all that you can.
right now I'm pissing about with as many champs that catch my eye. I ain't got no clue wha each does in each role, so I gotta figure it out before I hit the wasteland of competitive
Learn by class/Role not by champion to champion basis. Learn the basics. Now, some within a class fit a bit of a different role but knowing the basis of that role you can apply your knowledge to figure out what that champ is to do. It's hard to boil it down in a status length post.
