Where to get list of all possible functions available for Business Process

Where can I get all details on allowed formula systax and possible functions allowed to use
For example I was working to extract month & year from date and it was not so easy to understand best function allowed in business process formulas windows.

Looking for more details in addition to what we can see here:
https://academy.creatio.com/docs/8.x/no-code-customization/bpm-tools/bu…