Are C#and Java close enough??

Answer 1

Not enough to be good in C# automatically if I am good in Java ;)

Answer 2

Yes and no at the same time. A lot of the concepts are almost identical, but like any language compared to another - it will take some time to get used to it. If you master one of them, it will be much easier to learn the other. Try to concentrate more on the concepts and idiology, rather than syntax, as this will make you more flexible when learning a new language