Is aftercare also important after acne treatment?

I heard that aftercare is important after getting an acne treatment, so I'm wondering how much attention I need to pay.
I heard that getting an acne treatment isn't the end of it; you have to do home care as well.
I've been paying attention to cleansing, moisturizing, and sun protection because I heard they are especially important, but I'm not sure if I'm doing them properly.
I'm worried because I've heard that if you don't take care of your skin properly after the acne treatment, it can come back.
I'd appreciate some tips from those with experience on how to manage a post-acne treatment care routine.