want to create an EA, where do I start?

i have a relatively simple system that i want to try making an EA with but i have absolutely no idea where to start. are there any good websites that go over the type of coding one needs to create an EA or is there a book that goes over basic mql4?

you can learn how to code :
https://book.mql4.com/
https://quivofx.com/school/learn-mql4/

or not:
https://fxdreema.com/ (there are others likes this)

Basic programming knowledge and some time looking at different source code files, reading the documentation etc.

Also this little program helps see how coding is done in mql4 for a begginer, also it can be used to create simple EA's and indicators itself as well (instead of learning)