Casting is not inherently bad, it's just that it's often misused as a means to achieve something that really should either not be done at all, or done more elegantly.
If it was universally bad, languages would not support it. Like any other language feature, it has its place.
My advice would be to focus on your primary language, and understand all its casts, and associated best practices. That should inform excursions into other languages.
The relevant C# docs are here.
There is a great summary on C++ options at a previous SO question here.
