Hi Alankriti.

Well, JOSAA asks you to fill your choices of colleges and branches in a particular order. The order you choose is the order in which they decide the colleges and branches that you have a chance of getting. If your first preference is CSE in a particular college and your rank is enough to get it, then you'll get that college and branch. If not, then your second preference will be considered and so on.

So yeah, JOSAA counselling choice filling does affect the probability of getting a certain college.