Well learning c# helps you to get more knoweldge on internally how all process or activity in Uipath works and give a good knoweldge on how to code which is useful in Uipath and helps in creating custom activities.
C# is an object-oriented programming language from Microsoft that aims to combine the computing power of C++ with the programming ease of Visual Basic. C# is based on C++ and contains features similar to those of Java. some of the Best C# Books are:
1: C# in Depth
2: Programming C#
3: Head First C#
4: Beginning C# Object-Oriented Programming
5: Beginning C# 5.0 Database