The basics are not that complicated even if it might look like it. It is like Microsoft Word or similar word processor, lots of functions, but you only need to know a few to be productive.
Have a look at @Husky video tutorial:
https://discuss.eroscripts.com/t/how-to-script-in-openfunscripter-video-tutorial/16637
Or if you prefer a written one have a look at my text tutorial:
https://discuss.eroscripts.com/t/how-to-get-started-with-scripting/2234