ASA, CYA, RYA all recognize each others certification
They all share a common factor of certified instructors and a well written program available in many locations. US Sailing also could be added to the list as well.
Certification is a process of asserting minimal knowledge. If you go into it with that idea you'll come out learning
a lot and understanding what it is you don't know yet. It should build your own confidence and force you demonstrate things you may have felt you knew (sort of). All these courses get you started right. Starting with bad habits could be a disaster waiting for you out on the water
the language and the terminology helps you later on when you want to learn advanced subjects either through home study or other courses.