If you live in a rural area as many of us do in western Colorado, you may not be able to get your household sewage into a town sewer system. A septic system is a sewage system for a single property and its specifications have to be engineered. The requirements for a particular system are related to how many bathrooms will be permitted on the property. If you are buying a home, you’ll have to have the septic inspected. If the inspection fails in any way, some buyers will run away, but all septic systems will eventually need to be maintained. Plus if you want to live in a highly desirable rural area, you will have to come to grips with your septic system.
You can’t teach yourself everything to the point of execution, for that I would rely on specialists (an engineer and the excavator with experience in septic systems). Also consider the differences in the soils to remember that something learned on a video may not apply to your geographic area.
I think the work of literature I need to be recommending here is Charles Bukowski’s Hot Water Music. Can you make the disgusting decrepit shit of the world into literature? You can try.