The Americans with Disabilities Act is not a law. It is five laws (two of which you will likely NEVER use) that are kept in one three-ring-binder.
Never presume that understanding Title I gives you any insight into Title II or knowing the first two means you get Title III.
Section 501 (raise your hand if you knew that was a thing!), Section 504 and IDE(E)A are in separate binders, but heavily cross-referenced.