Hi aspirant,

Autonomous: University/ colleges refers to a university/ college which exercises independent control over its day-to-day operations and curriculum. It is generally associated with universities, institutions and implies that the sponsoring state does not have control over academic matters of the school.

Affilated College: An affiliated school or affiliated college is an educational institution that operates independently, but also has a formal collaborative agreement with another, usually larger institution that may have some level of control or influence over its academic policies, standards or programs.

An affiliated college has certain restrictions, for instance, in syllabus formation, it has to stick to university prescribed syllabus. Whereas an autonomous college has flexibility in introducing innovative curriculum. The exam schedules can be fixed properly in a convenient way. The fairness in paper setting and evaluation is fairly maintained.these are only major advantages apart from other small perks of studying in an autonomous college

Source: https://en.wikipedia.org/wiki/Affiliated_school

All the best

Hello aspirant,  autonomous colleges have their own admission criteria and have their own rules and regulations regarding the ranks and scores. Affiliated colleges work in the specific guidelines provided by top authorities and have no reference of their own ex- AKTU, EAMCET etc