see if you want to study in popular institute with good placement record then you need to appear in entrance test. most of the colleges releases admission form on the month of february to march. now coming to webdesign course, its can be done by any students who have passed 12th or in any course of graduation. when you will study bca you may come to know about lot of application of web designing etc. however you may join niit or cmc academy for web design courses which has many type of duration courses on programming language or web development.