What is the difference between python and arduino programming?
Arduino uses a language that is derived from Processing, which looks like C++.

Python is a different language, although both have similarities (both Object Oriented for example).

What is 'complex' depends on what your background is. C++ is in general more complex than Arduino, but most people using Arduino program in C++, so most examples can be found in C++, which makes support from other users easier.

If you are new to programming, I suggest using the 'standard' Arduino IDE.

To be complete, Arduino is not a programming language, it is a platform. In general, every language can be used to write Arduino code, but only a few have compilers for creating Arduino (machine) code.