Open source, how can I view "Transaction Create a new transaction" and "Sign Transaction"?
The original Bitcoin client did not have a debug console or many things that we see in modern Bitcoin software. Furthermore, it is a compiled software (C++ needs to be compiled) so you can't inspect the thing being run for its source code. However, Satoshi did publish the source code along with the pre-compiled binary. For transaction creation, you can find this in the repo you linked in src/main.cpp. It is the function named CreateTransaction. Another copy of the original distribution can be found on nakamotoinstitute.org. 

Lastly, Bitcoin Core is based on the original client's codebase. It's commit history goes all the way back to 0.1.5 so you can see code that is very similar to the original release and view the code for any version between 0.1.5 and modern Bitcoin Core.