Not even close. Amongst other things, the breeakdown in American football uses a "downs-for-distance" system, which makes the contact in that sport far more violent than in either Rugby Union or League. If you are serious about understanding the differences, there is a wikipedia article on exactly that point. See

No nothing is the same all the rules are changed for example 1. In rugby the person has to have the ball for you to tackle them in football you don't 2. You can pass the ball forward or backward in football in rugby you can only pass it backward 3. The way you kick a conversion kick football gets placed in front of uprights in rugby it gets placed up from we're the try was scored Those are 3 examples but there are many more

no the rules are different e.g you can forward pass. heres a link to all the differences