Hi, In addition to the documentation mentioned in the previous reply, SAS also offers a free e-learning course on how to create a custom task:
Course: Writing a Custom Task for SAS® Studio
Creating a task yourself for the first time is onerous, but it gets a lot easier once you have done it once.
I have taught this course in the past and have programs for this e-learning available on SAS OnDemand for Academics through a course. I'll email you separately with instructions.